Sandberg Solar Charger 21 W 2 x USB is a highly efficient solar panel that converts sunlight to electricity. It features 2 USB outlets that can be used for charging your USB devices, such as smartphone, tablet or powerbank. By connecting to a powerbank, you can save the electricity there for later charging of your smartphone or you can use it as a stabilizing intermediary when charging. The supplied snap hooks can for instance be used for attaching the solar panel to your backpack when you are on an adventure. This is green energy for your equipment!