Put it in the sun or wind it up to recharge.6min of winding or cranking generates 1hr of light. Internal battery stores solar & cranking power so you always have a charged self powered hand cranked flashlight source ready.With a convenient carabiner that can hook on a backpack or keychain, your super small flashlight is easy to travel with and a great addition to your hiking survival gear. Customize with an imprint of your logo and message for heightened brand awareness