Specifications: Power: 1W Voltage: 3-5V SNR: 96dB Transmission distance: about 5m with Red light on buttons ( click the physical button, the button light will be on for 2-3 seconds ) Attention for pre-order: * The product could not work with any tablet PC , Home TV , or car headrest , roof mount monitor ... * if your car radio player has key 1 wire , no key 2 wire , , Please do not buy , our product could not work with the car radio completely . * the product can work with android car radio player , or wince car radio player with key 1 ,and key 2 wires . Knowledges for installation: * before installation , please switch off your car power ,and avoid to burn the electronics board when making wrong wire connection * please make the wire connection according to wire diagram ( see the below wire diagram ) * after wire connection , please enter in the menu interface of steering wheel control on car radio screen,and set up these soft buttons on learning , click the soft button on car radio screen ,and then press the corresponding physical button on steering wheel control button . repeat to pair the buttons one by one . Color: As Shown Material: plastic Package Contents: 1*Wireless remote control set Only the above package content, other products are not included. Note: Light reflection 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.