The HydraCell WFL-100 Waterproof Flashlight floats for worry-free operation out at sea or in any water environment. A revolutionary, LED flashlight powered by our proprietary HydraCell fuel cell. The Waterproof Flashlight is a must have for emergency preparation or standby light sources. It can be stored for 25+ years in original packaging and still be ready to go when you need it most. This is not an ordinary flashlight, it is a reliable source of light when you need it most. The replaceable HydraCell Energy Cell can be stored prior to first use for 25+ years and is activated instantly to full capacity simply by dipping in water. Once activated, the cell will operate continuously under load, requiring only periodic re-hydration. After 200+ hours, depending on load & usage, a new HydraCell Energy Cell will immediately restore the WFL-100 to a like-new condition.