The little cap can protect the connector when not in use for expand the small portable charger's lifespan. The portable phone charger equipped with an real 5000mAh Capacity, can provide at least one full charge for most Phones. The phone battery pack which utilizes a slim and powerful UL-tested battery, the certified Intelligent chip ensures 100% compatibility with your Phone, providing you a reliable charge. Reinforced joint design that have passed 30000+ times plugging and unplugging tests for extra protection and durability. Built-in intelligent safeguards can effectively prevent your mini phone charger over-charge, over-voltage, over-current, and short circuit.