Rechargeable Lithium-Ion battery. Input: 5V/1A; Output: 5V/1A and 5V/2.1A; Capacity: 4400 mAh. Charge time differs by device. Must charge prior to first use. Duo USB Aluminum universal international emergency mobile smartphone battery charger. Features LED indicator light. 4 blue lights shine to indicate full charge. Lights will turn off one by one as power is drained from device use. USB charging cable provided. Instructions included. UL Certified (UL File # MH60484). Engraves Silver. **Shipping available via ground service only** WARNING: Refer to the item manual for safety and warning instructions.