This is a 5W, 6V Solar Panel. It's our largest 6V panel, and if you want to direct-charge high-power USB devices like cell phones, tablets, GPSs and other portable electronics, this is the panel for you. 5W of charging power means this panel, in full sunlight, can charge most portable devices in the same time it normally takes to charge from a wall charger. This panel is also compatible with the Raspberry Pi. Glass and EVA encapsulated for a 20 year estimated lifetime.