Serfas" True 250 Standard Light is what you need to see the road or trail at night. Lightweight, compact and super bright - the TSL-S250 will deliver when you need it most. It comes with a rechargeable Li-Ion Battery, USB Charger cable, USB Wall Adapter, Handlebar and Helmet Mounting systems and a limited lifetime warranty. Serfas is setting the benchmark in high-powered LED lighting technology by testing it lights in house using a 20" N.I.S.T. Traceable Standard Integrating Sphere. Hence the name "True" lights, when you buy a Serfas light - you are guaranteed to get what you paid for.