Feed escapements are used for individually feeding parts from hoppers, conveyors, magazines, tracks, and vibratory feeders. By separating parts at the ends of feed chutes or raceways, these pneumatic devices prevent jams and multiple feeds. Feed escapements are equipped with retractable and extendible components called fingers that provide positive part control. Standard mounting holes are designed to fit tooling shaped for specific part shapes and sizes. To accommodate the orientation of the feed chute, feed escapements may be mounted vertically or horizontally, or at a specific angle. Feed escapements are made of durable components and materials, and designed for use in production environments, factory settings, and material handling applications. Feed escapements are equipped with fingers, moving parts that are usually made of aluminum and which have a square cross-section. Some feed escapement fingers are spring-loaded. To minimize surface wear, finger holders are equipped with a flush-type oiler and ball closure. This design enables feed escapements to lubricate multiple fingers simultaneously. First, pressure forces both fingers in opposite directions. When the first finger is fully-extended, the second finger pushes a retractable locking pin or rod. Then, with the second finger fully-retracted, the pressure is reversed. This causes the first finger to retract and the second to extend fully. Feed escapements that are designated as field-repairable are sold with maintenance kits that plant personnel can use as necessary. Some devices are equipped with sensors or other special features. Feed escapements carry specifications for materials of construction, finger stroke, bore, and maximum air pressure. Typically, finger holders are precision ground and made of hardened tool steel. Both finger stroke and bore are measured in inches (in) or fractions of inches, or in metric units such as centimeters (cm). To reduce stroke, nylon sleeves can be cut to length and inserted behind the rod or piston. Air pressure is listed as a maximum amount and usually specified in pounds per square inch (psig). Additional parameters to consider when selecting feed escapements are dowel holes, air ports, clearance, sensor slots, power during extension, and power during retraction. Feed escapement accessories include tubing, pneumatic fittings, control valves, pressure safety valves, and a proximity switch.