These JET Drill Presses use a variable-speed motor with the stepped-pulley system, and come equipped with a continuously variable transmission. This enables use at a wide range of speeds, as well as the ability to change speed during operation. A scale-marked hand wheel that matches the desired machine speed is mounted to a reduction gearing system for precise operator control. This adjusts the gearing ratio between the motor's fixed pulley and the output shaft's variable pulley, changing the speed of the chuck. A tensioner pulley is implemented in the belt transmission to take up or release the slack in the belt as the speed changes.