• For Non-Metallic Containers
• Easy External Mounting
• Compact Design
• Power On and Signal LED Indicators
• RoHS Compliant

The CAP-100 series offers a unique level sensing solution for a wide variety of bottle types including plastic, glass and fiberglass. The non-contact sensor is ideally suited for medical applications such as waste, reagent or diluent liquids as well as dark, sticky or viscous fluids. The easy-to-calibrate sensor is available in both aqueous and non-aqueous versions and can be delivered with factory preset sensitivity for quick installation for OEM orders. The CAP-100 may also be used as a proximity sensor to detect the presence of solids such as paper or pulp.

Applications:

• Waste
• Reagents
• Diluent
• Detergent/Wash
• Coolant
• Printing Ink

• For Non-Metallic Containers
• Non-intrusive level sensing
• Optional Sight Glass Bracket
• Potentiometer for sensitivity adjustment

The CAP-150 series offers a unique level sensing solution for a wide variety of bottle types including plastic, glass and fiberglass. The non-contact sensor is ideally suited for medical applications such as waste, reagent or diluent liquids as well as dark, sticky or viscous fluids. The easy-to-calibrate sensor is available in both aqueous and non-aqueous versions and can be delivered with factory preset sensitivity for quick installation for OEM orders. The CAP-150 may also be used as a proximity sensor to detect the presence of solids such as pulp & paper.

Applications:

• Waste
• Reagents
• Diluent
• Detergent/Wash
• Coolant
• Printing Ink

• For Metallic and Non-Metallic Containers
• Food Grade Plastic Housing
• No Sensor Well Required
• RoHS Compliant

The CAP-200 Series is easily threaded directly into 1/2"NPT fittings for an easy level sensing solution within a wide variety of metal and non-metal tanks. The highly accurate sensor is built from durable Delrin material, and is available in both aqueous and non-aqueous versions. The easy to calibrate sensor can be delivered with factory preset sensitivity for quick installation by OEM. The CAP-200 may also be used as a proximity sensor to detect the presence of solids such as paper or pulp.

Applications:

• Waste
• Reagents
• Diluent
• Detergent/Wash
• Coolant
• Printing ink

• All Stainless Steel
• FDA Compliant for Contact with Food
• High Temperatures and Pressures

Rugged construction suitable for most corrosive liquids, and for high temperatures and pressures. All-stainless steel material of construction complies with FDA food contact regulations.

• Large Size
• 1" NPT
• High Pressure/Temperatur

These units solve the problem of point level sensing in tanks with inaccessible tops or bottoms, or at intermediate locations in larger tanks. Operation is positive and dependable. The float pivots with changing liquid levels, displacing a shuttle which magnetically actuates a hermetically sealed switch within the unit. Installation is through the tank side at the detection point. General purpose materials designed to provide reliable service in oils and water. Ultimate strength: for pressures up to 900 psig (62 bar) and temperatures up to 300°F (149°C). Explosion-proof models are available.

These units solve the problem of point level sensing in tanks with inaccessible tops or bottoms, or at intermediate locations in larger tanks. Operation is positive and dependable. The float pivots with changing liquid level, displacing a shuttle which magnetically actuates a hermetically sealed switch within the unit. Installation is through the tank side at the detection point. Rugged, all-stainless steel unit offers broad chemical compatibility at temperatures to 300°F (149°C).

Explosion-proof models available.

• Internal Mounting
• Stainless Steel Construction
• Complies with FDA Food Contact Regulations

Built for durability, our LS-7 Series switches utilize stainless steel, or zinc bodies. Ideal for any small tank or vessel destined for a rugged environment. All-stainless steel material construction of Type 11 complies with FDA food contact regulations.

Type 11 - 316 Stainless Steel body with 316 SS float.

• External Mounting
• 7/8" - 14UNF Thread
• SAE Mounting

Built for durability, our LS-7 Series switches utilize stainless steel, or zinc bodies. Ideal for any small tank or vessel destined for a rugged environment.

Type 6 - Zinc alloy body with polypropylene or nylon float. SAE Mounting.

• External Mounting
• 1/2" NPT
• Ideal for Small Tanks

Built for durability, our LS-7 Series switches utilize stainless steel, or zinc bodies. Ideal for any small tank or vessel destined for a rugged environment.

Type 8 - Zinc alloy body with nylon or polypropylene float.

• External Mounting
• Stainless Steel Construction
• Complies with FDA Food Contact Regulations

Built for durability, our LS-7 Series switches utilize stainless steel, or zinc bodies. Ideal for any small tank or vessel destined for a rugged environment. All stainless steel material construction complies with FDA food contact regulations.

Type 9 - 316 Stainless Steel body with 316 SS, nylon or polypropylene float.

• All-Plastic Wetted Parts
• 1 to 4 Actuation Levels
• Lengths to 20" (508 mm)
• U.L. Recognized; CSA Listed Versions Available

Gems™ complete line of small, polysulfone liquid level switches are designed for the high quantity needs of the OEM, LS-300 Series switches are the ideal level sensor for shallow tanks and reservoirs. Compact and versatile, these low-cost, plastic level switches offer a broad choice of mountings and float materials.

• Low Particle Generation-One piece Molded Design
• Corrosion Resistant
• 1 to 4 Actuation Levels in a Single Unit
• Lengths to 24" (610 mm)

Applications:

• Semiconductor Process Equipment
• Pure Chemical Delivery System
• Wafer Cleaning and Etching Systems
• Cabinet Leak Sensing

• Up to 4 Actuation Levels
• Integral Siphon or Fill Tube
• Customized Mountings
• Custom Configurable

Save valuable space and costly installation/maintenance time with these highly customizable sensors. LS-350 units combine siphon tube and up to four liquid level sensors as a single component. The complete unit installs through a single opening in the fluid container.

Simple and clean - a single component that enables remote monitoring of a tank's fluid content while allowing access for container filling and draining. These units are custom configured to fit the container of your choice, with a wide range of mountings, fluid and electrical connectors, materials and lengths.

Applications:

• Immuno-Chemistry/Cytology
• Hematology
• Automated Urine Analysis
• Laboratory Automation

• Stainless Steel or Brass Mountings and Stems
• 1 to 5 Actuation Levels
• Lengths to 48 Inches (1219 mm)
• U.L. Recognized; CSA Listed Versions Available

These compact units feature the rugged durability of stainless steel or brass construction in a lightweight package. Ideal for tanks less than 4 feet (1.22 m). LS-700 Series switches are exceptionally versatile because of the many useful options available. These options can extend the functionality of your Gems™ LS-700 Series custom switch.

• Stainless Steel or Brass Mountings
• 1 to 6 Actuation Levels
• Lengths to Over 11 Feet (3.35 m)
• U.L. Recognized; CSA Listed Versions Available

Rugged construction and multiple options provide the LS-800 Series with exceptional versatility. Longer and more substantial than other metallic models, the LS-800 is capable of supporting larger, more buoyant floats, and is physically stronger for better reliability in contaminated or turbulent media. This series offers SPST or SPDT switches, and a choice of mountings, floats and materials that can be configured for a wide range of applications in water, oils, chemicals and corrosive liquids.

• NSF Approved All-PVC Wetted Parts Available
• 1 to 7 Actuation Levels
• Lengths to 60 Inches (1524 mm)

Inexpensive, all-PVC LS-800PVC Series switches bring reliable level sensing to corrosive liquids. These durable, yet economical, switches use the same high-quality, dependable reed switches found in Gems™ most expensive models. NSF-approved wetted parts make the LS-800PVC suitable for potable water applications.

• All-Plastic Wetted Parts - PVC, Polypropylene or PVDF
• 1 to 6 Actuation Levels
• Lengths to 70 Inches (1778 mm)

Specifically designed for corrosive liquids and vapors. Three standard model types in a choice of materials offer broad chemical compatibility.

• Ideal for Controlling Filling Operations and Preventing Overflow
• Ideal in Oils and Water

These units are ideal for use in oils and water. Precisely monitors liquid level and is ideal for controlling filling operations and preventing overflows. Permanent magnet attaches unit securely to steel tank wall at exact level required.

• Durable sealed design – IP67, IP6K9K
• Developed for the most rugged coolant applications
• Tolerates coolant coating
• Small size – 2˝ (51 mm) long

The CAP-300 capacitive level sensor is one of our most durable and reliable point level sensors. Compatible with coolants, the CAP-300 is the ideal OEM solution for power generation equipment, off-highway vehicles and cell phone tower generators and can be mounted in any position. With nearly zero maintenance, the sensor is small in size, tolerates coating and will remain reliable even in the standby mode. Compatible with temperatures up to 257°F (125°C) the capacitive based sensor is suited for the most challenging environments. Available with a variety of mounting types and electrical connections, the CAP-300 is the ideal solution for coolant monitoring. NOW! Available in 316L S/S.

• Overfill protection for refrigerant tanks
• U.L. Recognized
• Provides 80% Full Shutoff Capability

Overfill protection for refrigerant tanks. The LS-700F enables safe compliance with EPA directives to recover refrigerants. These units are designed to fit standard 30# and 50# D.O.T. approved refrigerant tanks. They provide 80% full shutoff capability when used as an integral part of a recovery system.

• Dependable Long Service Life
• Fits Small, Interstitial Spaces
• Easy Maintenance

The Gems™ LS-10 liquid sensor accurately detects the presence of liquid in fiberglass double-wall tanks, containment sumps and double-wall pipes. Dry contact switching ensures dependability throughout its long service life. This reusable sensor easily fits small, interstitial spaces and senses liquid hydrocarbons or water. The unit is unaffected by hydrocarbon vapor, thereby reducing the risk of false alarms. The LS-10 sensor's rounded design makes it easy to remove, clean and reinstall after an alarm condition is triggered, or for maintenance.

Applications:

• Fiberglass Double-Wall
• Tanks Containment
• Sumps Double-Wall
• Pipes
• Piping Sumps

These polysulfone level switch units are both compact and economical. They feature a variety of mountings, power requirements and electrical terminations to make it easy to find a perfect match for your application.

The ELS Level Switch Series is low cost, compact, optical, level sensors with built-in switching electronics. With no moving parts, these small units are ideal for a variety of point level sensing applications especially where dependability and economy are a must.

These level switch units are suitable for high, low or intermediate level detection in practically any tank top, large or small. Installation is simple and quick through the tank top, bottom or side. Solid state-switching ensures dependability over long service life.

The sensor offers ±1 mm repeatability and broad liquid compatibility. They are not recommended for use in any liquid that crystallizes or leaves a solid residue.

Applications:

• Medical Laboratory
• Food and Beverage Systems
• Pharmaceuticals
• Petrochemicals
• Leak Detection
• Hydraulic Reservoirs
• Machine Tools

• Flange Mounting
• No Threads Needed
• Ideal for Thin Wall Tanks

The easy solution for thin wall tanks 1/4" thick (6 mm): ELS-1100FLG Series Level Switch. No threads needed with these flanged units. Slip through a .75" (19 mm) hole and tighten the jam nut; a Viton^® gasket forms a tight seal. Ideal for sheet metal, molded plastic tanks and medical applications where elimination of exposed threads removes potential bacterial breeding grounds.

ELS Series Level Switches are low cost, compact, optical level sensors with built-in switching electronics. With no moving parts, these small units are ideal for a variety of point level sensing applications especially where dependability and economy are a must.

Level switches are suitable for high, low or intermediate level detection in practically any tank top, large or small. Installation is simple and quick through the tank top, bottom or side. Solid state-switching ensures dependability over long service life.

The sensor offers ±1 mm repeatability and broad liquid compatibility. They are not recommended for use in any liquid that crystallizes or leaves a solid residue.

Applications:

• Medical Laboratory
• Food and Beverage Systems
• Pharmaceuticals
• Petrochemicals
• Leak Detection
• Hydraulic Reservoirs
• Machine Tools

• Temperatures to 212°F
• HTS Version - 1/2" Long
• UL Approved

Slightly larger than the ELS-1100, the "HT" or High Temperature version is made from high performance Isoplast plastic. While maintaining broad chemical compatibility, these units also handle fluid temperature to 212°F (100°C). They feature 3/8" NPT mountings and the shortest of any of our electro-optic switch bodies-HTS versions are a mere 1/2" long!

ELS Series Level Switches are low cost, compact, optical, level sensors with built-in switching electronics. With no moving parts, these small units are ideal for a variety of point level sensing applications especially where dependability and economy are a must.

Level switches are suitable for high, low or intermediate level detection in practically any tank top, large or small. Installation is simple and quick through the tank top, bottom or side. Solid state-switching ensures dependability over long service life.

The sensor offers ±1 mm repeatability and broad liquid compatibility. They are not recommended for use in any liquid that crystallizes or leaves a solid residue.

Applications:

• Coolant Reservoir Monitoring
• Medical Diagnostic and Sterilizer Equipment
• Low Level Lubricant Warning on Machine Tools
• Low Level Warning in Food Warmers

• Teflon^® Body and Prism
• Ideal for Ultra-High Purity Applications
• Chemically Resistant

When high purity or resistance to chemical attack is vital, ELS-1100TFE sensors are the ultimate solution. They feature a pure Teflon^® body and prism construction. Even the Hypalon^® vapor barrier and Teflon^® coated lead wires give evidence to the care we've taken to make this the perfect liquid level sensor for pharmaceuticals, semiconductor manufacturing, food and beverage, chemical processing, or anywhere purity or chemical resistance is the major criteria.

• Fused Glass Prism for High Pressures
• Excellent Price-to-Performance Ratio
• Ideal for Corrosive Environments

The enhanced ELS-1150 series is the highest performing electro-optic level switch from Gems™ Sensors. At just 1.38" (35 mm) long, the ELS-1150 has been upgraded with a micro-processor board design to provide a wide range of capabilities including sinking, sourcing and time delay outputs. The strong fused glass prism eliminates leak potential and is capable of handling extreme temperature and pressure applications up to 2500 psi (172 bar). The ELS-1150 series is available in FM and EP versions with wide voltage ranges (ELS-1150XP) for Oil & Gas. Built with solid state reliability, the sensor is available at an affordable price in nickel-plated carbon steel or stainless steel. The compact size of the sensors makes them ideal for monitoring the small, pressurized vessels found in HVAC, refrigeration and hydraulic applications. The sensors are most commonly used for low, high and intermediate level detection.

The stainless steel version, (ELS-1150SS), is excellent for applications requiring corrosion resistance and is ideal for acids, solvents and dielectric water applications. Higher temperature versions are available up to 257°F (125°C). Contact our factory experts for additional ordering information.

Applications:

• Hydraulic and lubricating oil reservoirs
• Critical fluid level monitoring on machine tools, compressors, chillers and other industrial OEM equipment
• Ideal unit capable of handling corrosive liquids such as: acids, solvents, and dielectric water applications
• Medical Equipment; Anesthesia, Histology

Markets:

• Oil & Gas
• OHV
• Industrial

• Smallest Size
• TPE Over-Molded Electronics
• Durable Enough to Handle Harsh Environments

Not only is the ELS-950 the smallest electro-optic liquid level sensor in our arsenal, but it also carries the highest operating temperature capability at 230°F (110°C). The Polysulfone housing ensures this sensor is compatible for use in a broad range of medias. The ELS-950's design features an over-molded electronics insert, TPE insulated wires, and fluorosilicone O-ring seals that create a water-tight, environmentally resistant assembly. The ELS-950 is an excellent value making it a perfect choice for industrial OEMs desiring an extremely small, 'no-moving-parts' sensor rated for high temperatures.

Applications:

• Coolant reservoir monitor and warning
• Medical diagnostic, sterilizer, washers and dialysis equipment
• Low lubricant warning on machine tools, generator sets, on- or off-highway vehicles
• Low level warning in hydraulic reservoirs
• Plastic overflow bottles, plastic radiators

• Rugged brass housing
• Smallest Size
• TPE Over-Molded Electronics
• Durable Enough to Handle Harsh Environments

The ELS-950M Series represents Gems™ smallest electro-optic level sensor developed to monitor a broad range of media including OHV type fluids.

Our UL approved design features a rugged brass housing, a TPE over-molded electronics insert, TPE insulated wires, and flourocarbon o-ring seals that create a watertight, environmentally resistant assembly, ideally suited for use in harsh environments.

The ELS-950M is excellent for industrial OEMs requiring a solid-state sensor for small space and high temperature environments.

Typical Applications

• Coolant reservoir monitoring and warning
• Medical diagnostic, sterilizer, washers and dialysis equipment
• Low lubricant warning on machine tools, generator sets, on- or off-highway vehicles
• Low level warning in hydraulic reservoirs
• Plastic over flow bottles, plastic radiators
• Leak detection for drip pans

• Ideal for Large or Small Tanks
• Compact Aluminum Housing
• Inline NPT Ports

Bottle type level switches are ideal for large or small tanks or where access to the inside is impractical or impossible. These units mount completely outside the tank, at the level actuation point. LS-159000 Series - Low Cost, Compact Aluminum Housing. Inline NPT Ports.

• Rugged Durability
• Ideal for Oils and Water
• Broad Heat and Pressure Capabilities

Small compact level switches combines reliability with low cost. The unit is equipped with a hermetically sealed SPST 20 VA reed switch and is operated by permanent magnets within the float. As the float is raised and lowered with changing liquid level, the hermetically sealed single point level switch closes as the float comes into proximity of the reed switch. The switch logic can be reversed on most models by inverting the float on the stem via a removable float retaining clip. The 20 VA switch is suitable for most solid state control circuits, by using a relay interface the switch can be made capable of switching higher current loads. The unit is easy to install and can be top or bottom mounted. Using an extension pipe and proper sealing techniques the unit can be extended into the tank for high, intermediate, and low level actuation points. The LS-1700 brass/buna version is ideal for low hydraulic fluid warning and other hydrocarbon applications. It can be factory custom configured for volume OEM applications and used as a water or oil level switch.

• Low Particle Generation
• Corrosion Resistant PTFE

Offers broad chemical compatibility for general purpose use. Also ideal for oils and water. A medium-size solution for ultra-pure liquid level sensing. Made of corrosion resistant PTFE for low particle generation.

• All Stainless Steel
• FDA Compliant for Contact with Food
• High Temperatures and Pressures

Ideal for shallow tanks or restricted spaces, or for low-cost, high volume use. Rugged construction suitable for most corrosive liquids, and for high temperatures and pressures. All-stainless steel material of construction complies with FDA food contact regulations.

• Withstands Rough Service
• Intermediate Size
• Excellent Stability

Excellent stability for general use in oils and water. With large float displacement, switch withstands rough service; suitable for high viscosity liquids. Intermediate in size, LS-1800 switches provide long life and dependability to meet a broad range of requirements.

• Ideal for Viscosity Fluids
• Withstands Rough Service
• Intermediate Size

Excellent stability for general use in oils and water. With large float displacement, switch withstands rough service; suitable for high viscosity liquids. Intermediate in size.

• All Plastic Material
• Resists Build-Up
• Ideal for Viscous or Corrosive Liquids

When all-plastic material is desirable and tank space is not restricted. Resists build-up of foreign material or sticky media. Float travel remains uninhibited in viscous or corrosive liquids. SPDT switch.

• High Temperature/Pressure Capabilities
• Materials of Construction Comply with FDA Food Regulations

For high performance applications, these models provide high temperature and pressure capabilities. Materials of construction comply with FDA food contact regulations. Exceptionally accurate and rugged for higher temperatures and in pressurized or corrosive liquids. For oils, water and chemicals.

• Lightweight
• Stable in Non-Static, Highly Contaminated Liquids
• Bracket Mounted

These units are ideal for use in oils and water. Small, lightweight, and extremely stable in non-static, highly contaminated liquids. Slosh shielding minimizes effects of turbulence and helps prevent interference by foreign material. Bracket-mounted to any convenient surface.

• Engineered Plastics
• Ideal for Shallow Tanks
• Low Cost/High Volume Use

The durable construction of these reed switch designs ensures long, trouble-free service. Because the effects of shock, wear and vibration are minimized, these hermetically sealed switches provide precise repeatability with no more than 1% deviation. The switch actuation points remain constant over the life of the unit.

Ideal for shallow tanks or restricted spaces, or for any low-cost, high volume use. LS-3 Series are available in FDA/NSF compliant materials upon request, consult Gems™ for details.

• Solid Foamed Polypropylene Float Offers Narrower Design - only 3/4" (19 mm) Wide for Tight Spaces
• Polysulfone Float: For Water Based Liquids, With Limited Use in Oils and Chemicals
• Polypropylene Float (hollow): Features a Low Specific Gravity Float Offering Broad Chemical Compatibility.
• Polypropylene Float (Solid): With Polypropylene Stem and Float, Switch Offers Broad Chemical Compatibility.
• Buna N Float: Ideal for Oils and Fuels
• ALL-PVDF: Stem and Float of Corrosion-Resistant PVDF for Ultra-Pure Applications.

• Small Size
• Cushioned Float
• Ideal for Oils and Water

These units are ideal for use in oils and water. Cushioned float and switch for turbulent liquids or excessive vibration. Easily grounded. Ideal for tank trucks, construction equipment or mobile applications.

Applications:

• Tank Trucks
• Construction Equipment
• Mobile Equipment

• Controls Two Independent Loads up to 5 Amps Each

A single pole double throw relay enables this level switch to control two independent loads up to 5 amps each, switching N.O. for one load and N.C. for the other. This unit is designed to operate with a load connected to each of the two outputs. These loads must be 10 watts, minimum, for correct SPDT switching. One load used alone must be connected to the N.O. terminal. With this load, which may be less than 10 watts, the unit will operate the same as an SPST unit.

• Float Design Eliminates Problems Associated With Liming, Calcifying Applications
• NSF and WRC Material Compliant

This compact Side Mount Level Switch is optimized for calcifying hot water applications. The Drop Float design keeps critical sensor elements out of the water thus eliminating liming or mineral deposit problems that can affect other level switches. This switch is ideal for use on food warmers, hot water heaters, steam cookers and small boilers or wherever water evaporation occurs. Made of Noryl and NSF and WRC approved for use in potable water.

Applications:

• Food Warmers
• Hot water Heaters
• Steam Cookers
• Small Boilers

• Ideal for Potable Water
• Broad Chemical Compatibility

This compact Side Mount Level Switch is optimized for calcifying hot water applications. The Drop Float design keeps critical sensor elements out of the water thus eliminating liming or mineral deposit problems that can affect other level switches. This low-cost unit is ideal for high volume use in small tanks and vessels. Engineered plastics construction offers broad compatibility in water, oils and chemicals.

Applications:

• Food warmers
• Hot water heaters
• Steam cookers
• Small boilers

• Nylon is Ideal for Oils and Fuels
• NSF-Approved Polypropylene is Ideal for Potable Water and Broad Chemicals
• Versaplast is ideal for corrosive fluids

These low-cost units are ideal for high volume use in small tanks and vessels. Engineered plastics construction offers broad compatibility in water, oils and chemicals.

Type 3 - Polypropylene, Nylon or Versplast

• Nylon is Ideal for Oils and Fuels
• NSF-Approved Polypropylene is Ideal for Potable Water and Broad Chemicals
• Versaplast is Ideal for Corrosive Fluids

These low-cost units are ideal for high volume use in small tanks and vessels. Engineered plastics construction offers broad compatibility in water, oils and chemicals.

Type 5 - Polypropylene, Nylon or Versaplast

• NSF-Approved Polypropylene
• Ideal for Potable Water and Broad Chemicals

These low-cost units are ideal for high volume use in small tanks and vessels. Engineered plastics construction offers broad compatibility in water, oils and chemicals.
Type 7 - Polypropylene or Nylon; conduit connection.

• Particularly well suited for rough service.
• Ideal for use in chemical and plating applications.

When all-plastic material is desirable and tank space is restricted this large size float is ideal for use with aggresive fluids or ultra-pure liquids.

• Ideal for Use in Oils and Water
• Slosh Shield
• Supplied with Waterproof Cable

These units are ideal for use in oils and water. With a compact-sized float, slosh shield and weighted collar, the LS-750 provides liquid level detection for a wide variety of applications. Suspend in stand pipes or sumps for leak detection duty, or drop into wells for ground-water monitoring. Supplied with 25 feet (7.62 m) of waterproof cable.

• Bent Stem / Side Mount Design
• Specific Gravity as low as .45
• Stainless Steel or Brass

Type II version shown. These units perform in liquids with specific gravities as low as 0.45; switches protrude into tank less than 3 inches (76 mm).

• Ideal for Large or Small Tanks
• Mounts Outside the Tank
• 3/4" Brass or Stainless Steel NPT Ports

Bottle type level switches are ideal for large or small tanks or where access to the inside is impractical or impossible. These units mount completely outside of the tank, at the level actuation point.

Single Level, Brass or Stainless Steel Housing 3/4" NPT Ports.

• Ideal in Oils and Water
• Level Monitoring and Temperature Switch in a Single Unit
• Intermediate Size

These units are ideal for use in oils and water. Level monitoring and temperature switch in a single unit. Intermediate in size; single-setting temperature sensor is in bottom of stem.