The solar USB power bank comes with two USB ports. It features with super large capacity, suitable for sport, travel, and other outdoor activities, you can easily charge for your mobile phone anytime and anywhere. It supports solar fast charge, safe and environmentally friendly. With dual USB ports, you can easily charge for two devices at the same time, or share this backup power with your families or friends. Independent CPU security system protects your devices from overload, overcharge, overheat and short-circuit while charging.