This is a 14 tooth 1/2" ID drive sprocket that mates with a #25 roller chain (bicycle chain). With a drive sprocket on a motor and an roller chain, you can make things move.
This drive sprocket has 14 teeth at a pitch of 1/4" (.25 inches). You can calculate the travel of one revolution by multiplying the number of teeth and the pitch.
For instance: You have a motor with a 1/2" shaft and looking for the fewest number of teeth to achieve the highest possible mechanical resolution. The sprocket has 14 teeth with .25" pitch for a total of 3.5 inches of travel in one turn of the motor. Here are the resolutions at varying microsteps (in steps per inch): Full Step - 57.143, 1/2 - 144.286, 1/4 - 228.571, 1/8 - 457.143, 1/16 - 914.286, 1/32 - 1828.571.
This drive sprocket also has two set screws. The set screws are #10 UNC (Unified National Coarse - standard type) and uses an allen wrench to tighten.
The bore (inside diameter) is 1/2" (.5 inches). This drive sprocket will fit on a shaft that has a 1/2" diameter. This sprocket will fit on our NEMA 34 stepping motors.