Voltaic 1027 Switch 6W Solar Charger, Gray 6W / 6V solar panel is waterproof, lightweight, and built to withstand abuse. Designed to power and charge thousands of devices that charge from USB, including various handheld devices and smartphones. Includes a removable 4,000mAh, 15Wh universal battery that can be used to store power and charge devices The battery can also be charged from any USB port with the included Micro-USB adapter. 3 hours in the sun fully charges a typical smartphone and 20 minutes in the sun provides about 1 hour of typical smartphone use.