Bluetooth and 2.4G Modes Shift: - Use AAA battery * 2; - BT Switch click : Left ( Blue ) = BT mode, Mid = Off, Right (Green ) = 2.4G mode; - BT pairing : 1. turn on BT switch; 2. Long press Fn + Prtsc/ Scrlk/ Pause for 3s ( indicator flashing), then click the keyboard name on your computer to pair. Indicator on for 3s and then off. If pairing fails, the indicator flashing 3s and then off. 3. quick press Fn + Prtsc/Scrlk/Pause to shift between 3 devices.(Chemicy Gaming)