The Epsilon rechargeable mobile power bank's lithium polymer batteries give you 4,000mAh of backup power for your mobile phone or other digital device. It has a strong but lightweight aluminum case and features a smooth metallic surface and charging indicator lights. Includes a micro USB cable to charge the power bank. Output is rated at 1A. This product has undergone the most rigorous testing in the industry and is FCC VOC, MSDS, UN38.3, Prop 65, 7P, UL60950-1, UL1642, CEC/BC certified and UL listed.