Features: for Smart knob, match the for smart scene, open the for smart scene with one for key. You don'for t need to click the scene mode on the phone, just click the for smart knob to open the for smart scene. For example, movie mode turn on the TV, turn off the lights in the living room, close the curtains, turn on the TV ambient light, and turn on the sound. Click the for smart knob to do it. Five different opening modes of the for smart knob. Single Press, Double Press, Long Press, Rotate Press and Rotate. Five scenarios can be set, one to meet multiple needs is indispensable for you! Control lights, electronics and small appliances from anywhere. The battery can be used for a long for time, so there is no need to replace the battery frequently. No need to wire in. It can also be placed on the table, pasted on the wall, anywhere within reach! Specifications: Material:ABS Size:Approx4x4x2.65cm/1.57x1.57x1.04inches Color:Black Package Includes: 1x Knob Switch note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings.