... + gush environmental feel is transparent oil (comfortable)Colors: Optional Power switch: Yes USB charging function: Yes Certified FCC, CE, ROHS, ... is about 4-5 hours. 5. Dedicated Home key to switch the screen into multiple applications. 6. Lightweight, quiet, waterproof ... : 20% -50% Instructions for use: 1. Turn on the power switch, power indicator lights and Bluetooth pairing 5 seconds, then goes off ...