This is the Kimbrough 90-tooth 64-pitch Precision spur gear.
Features: Molded from 4/6 nylon for high degree of strength and wide range of operating temperatures
Includes: 90-tooth 64-pitch spur gear
Specs:
Gear Pitch: 64
Number of Teeth: 90
Outer Diameter: 1.46 (37.2mm)
Center Hole Diameter: 0.38 (9.7mm)