The Planet Bike BRT-3H Taillight includes batteries, and self-leveling helmet mount, seatpost bracket, and a pocket clip.Soft-touch flash/constant/off switchFeatures a reflector integrated into the lens and Scotchlite reflective side stripsIncludes batteries, and self-leveling helmet mount, seatpost bracket, and pocket clipBrighter LED"sItem SpecificationsWeight48gBattery1AAABulb3 LEDRun Time100+