Internal Gears, Modules 1 Through 3

Featured Product from QTC METRIC GEARS

Precision internal gears from QTC Metric Gears are stocked in 22 sizes in modules 1 through 3. These 20° pressure angle internal gears, identified as the SI and SIR Series, are made from S45C steel which are black oxide coated and have tooth hardness less than 194HB. They can be combined with available spur gears to make planetary gear drives. Both series can be cut to make segment gears or corner racks. The SI Series conforms to JIS N8 grade, and the SIR Series conforms to JIS N9 grade standards.

QTC Metric Gears is your complete source for metric gears and gear products. With 9700 configurations of 150 standard items we are able to meet the ever increasing demand for metric gears for both replacement and OEM production quantities in power transmission applications.

Quotes, online orders, and 3D CAD models are available on our estore at

QTC METRIC GEARS, a Designatronics company
250 Duffy Avenue, Hicksville NY 11801
Phone: +1 516-437-6700 • Fax: +1 516-328-3343