USB-C RECHARGEABLE LI-ION BATTERY series Link up with 4 speaker system for fast charging Built-in smart chip for stable performance Smart Indicating LED for checking charging status Multiple Safety protection ECO-friendliness BY-01 1.5V Li-ion AA Energy: 2220mWh Input: USB C 5V 0.5A Output: 1.5V 2A Max BY-02 1.5V Li-ion AAA Energy: 666mWh Input: USB C 5V 0.1A Output: 1.5V 1.5A Max BY-03 9V Li-ion Energy: 4500mWh Input: USB C 5V 175mA Output: 9V 500mA Max BY-04 1.5V Li-ion D Size Energy: 7400mWh Input: USB C 5V 580mA Output: 1.5V 2A Max BY-05 3.6V Li-ion 21700 Energy: 18500mWh Input: UCB C 5V 1.5A Output: 3.6V 7.2A Max