Check the listing for details. PWM DC12-40V 3A Motor Speed Contoller Adjustable Variable Speed Control Switch. Condition: New. Listed at 9.63 USD. Input supply voltage: 12V-40VDC(max)PWM frequency: 21KHz ; Duty Cycle range:5%-100%Size: 7×4×3cm ; Net weight: 2.54 ouncesThe maximum output power: 120W; Power-On LED indicatorIncorporate a 10A fuse, and with the protection function of reverse connect power supply.CCM2NJ DC Motor Speed Regulator provides variable speed capability for DC motor. Control the forward or reverse direction and the stop of DC motor by switch. Equipped with aluminum shell and connection label, installed easily. Operating instruction:Before you attempting to wire the controller, make sure power is off. Turn on the power. The LED lights, the power is OK. Adjust the potentiometer. Color: SilverMaterial: Plastic + MetalPackage Including: 1 x DC Motor Speed ControllerNote: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.