This is a high quality plastic worm gear. Use it to get the desired speed and torque from your motor. Worm gears are along with pinion or spur gears to change the rotational plane by 90 degrees. It comes with a 6mm bore and a set screw which makes it easy to attach the gear to motors and axles of various diameters. Perfect for use in science projects, robotics, etc
The outer diameter of this gear is 19 mm. It has a central hole/bore of diameter 6 mm. Fits perfectly with all our 6 mm axles and motors with 6mm shaft.