CPEX Foldable Bluetooth Keyboard, Portable Mini Pocket Travel Keyboard for Android Wired USB, Wireless Handheld Multi-device Keyboard  (Black)

Multi-Device Connection 1. When connecting the first device, first press Fn+A and then press Fn+C to start the connection. 2. Before connecting the second device, press Fn+S once, then press Fn+C to start the connection. 3. Before connecting the third device, press Fn+D once, then press Fn+C to start the connection. 4. To use multiple devices at the same time, press Fn + A / S / D to switch to the connected devices freely. 5. Select the system according to your device: press Fn + Q / W / E / R (iOS / Andriod / Windows / Mac) at the same time, then you can use your keyboard comfortably. The travel folding keyboard has a built-in rechargeable lithium battery. 140 mAh large-capacity battery can provide more than 60 hours of effective use time after 2 hours of charging.