3020-00-789-4175 (221-01-181)
NSN 3020-00-789-4175 (NIIN 00-789-4175) is a spur gear in Federal Supply Class 3020, Gears, Pulleys, Sprockets, And Transmission Chain — a gear, cylindrical in form, with straight teeth on the outer surface parallel to the axis of the gear. Manufacturer part number 221-01-181 (Recon/Optical, Inc., CAGE 11871).
Key specs: 38 to 42 rockwell c overall hardness; full characteristics table below. NIIN assigned January 1962; DEMIL A (none required); export Schedule B 8483.40.9000.