Features: Suitable range: For nominal voltage 3.6V 3.7V lithium battery(Including 18650,26650, lithium polymer batteries) Precautions: 1.Strictly according to the diagram wiring: 0V/4.2V/8.4V/12.6V,Otherwise it will cause damage to the chip. 2.After connection,it need to first charge activation, then will have the output. Attention: Do not mix the good battery and poor battery to use. The internal resistance of 3 battery capacity are closer will be better. Please buyers know the professional knowledge of this module before buying Specifications: Material:Metal Charging voltage: 12.6V Maximum output current: 20A Maximum output power / charging power: 252W Size: 5.9x2cm/2.32x0.79inch Quantity: 1 Pc Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Contents: 1 x PCB for Protection Board