colour: black Material: Plastic size: 44x30mm Notes for using 3.7V lithium battery power supply 1.When using the battery power supply, the battery voltage is lower than 3.3V and the decoder board switches off automatically. After charging or fully charging, switch on / off contact for 2 seconds. 2. When using the battery power supply, if the battery voltage is too low, there may be "sizzling" noise, in this case, the battery needs to be . 3. Since no lithium battery charging protection circuit is designed on the decoding board, lithium battery with its own protection board is recommended. 4.If your rechargeable battery supports Micro-USB direct charging, you can use Micro-USB to charge the battery directly. Package Contents: 2 x Decoder board 2 x remote control Only the above package content, other products are not included. Note: Light 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.