ITEM NAME:USB 5V 2A Mobile power Battery protection DIY Charger PCB Board Module N %o Description: Output: DC 5V / 2A (Maximum) Input DC 5V / 1A Android line interface 1: batteries that can be used: polymer batteries, lithium batteries, mobile phone batteries, flat batteries, etc. Access Battery Requirements: 3.7-4.2V Polymer Batteries: No other batteries, such as 1.2V Ni-MH batteries, 3.2V Li-Fe batteries, power batteries, all dry batteries, 12V lead-acid batteries 2: Charge and discharge protection: lithium battery protection IC built-in circuit board, over-voltage protection, over-current protection, under-voltage protection, etc. 3: Charging Input Requirements: The best match is the charger above 5V1A. Any other 5V constant voltage power supply can be used as charging input power supply. Size:72*18*5.5mm B+: Battery positive pole, B-: Battery anode Package includes: 1 x Charger PCB Board Module.Output: DC 5V / 2A (Maximum). Input DC 5V / 1A Android line interface. B+: Battery positive pole, B-: Battery anode.