ZNTER Ultra-Efficient 9V 400mAh USB Rechargeable 9V Lithium Polymer Battery – black&green. Features: Replace dry battery perfectly. Energy-saving and durable. With constant voltage 9V and USB wires for convenient charge. Equipped with Micro USB charge port,which is convenient and efficient. Intelligent power chip inside to make sure the charge up to 99% with constant voltage Cycle life>3000,increase 200% than normal battery which fits the low-carbon life style. Charge it anytime anywhere, no need to afraid that whether the battery run out. Short-circuit protection inside and it is unwarming for long time charging. Specification: Material: Fireproofing plastic shell Cell type: A+ Lithium Polymer battery cell Input: Micro USB(5V) Output: 9V Charge voltage: 4.25V Battery capacity: 400mAh Energy capacity: 3.6Wh Battery life: >3000 times Charge time: 1.5 hours Compatibility: 9V battery Color: Black and green Size: 48mm*25mm*16mm Package included: 1 x 9V rechargeable battery Note: According to different conditions, Battery capacity can be divided into actual capacity, theoretical capacity, also called rated capacity. Battery capacity refers to the battery storage capacity. The unit is “mAh”, 1Ah = 1000mAh, so there are some differences between rated capacity and actual capacity in Li-ion Battery. It is normal and reasonable.