Item Type: DC Motor Speed Controller Input: 110V AC Output: 110V DC Overall Dimension: Approx. 100 x 60 x 114mm / 3.94 x 2.36 x 4.49in Opening Size: Approx. 81 x 53mm / 3.19 x 2.09in Installation Method: Panel Screw Installation Package List 1 x DC Motor Speed Controller 1Higher Accuracy: Wide in speed adjustment range, the DC motor speed controller ensures the stable working performance with high efficiency. 2Standard Design: Supports 110V AC input and 110V DC output, the motor speed regulator enables direct start up when there is DC voltage. 3Reversible Uses: To reverse the CW and CCW rotation direction of your DC motor, you can changing the wiring between M+ and M- terminals. 4Wide in Fitting: Suits perfectly for 50W, 100W, 120W, 200W, 300W, 400W and so on, the motor speed control switch has flexible application. 5Easy to Install: Compact in size and light in weight as well, the DC motor speed controller is very convenient to install within minutes.