PowerFlare PF-200 Safety Lights are essential for Law Enforcement vehicle fleets. Clients also include, Fire, Federal and Military. Besides checkpoints and roadside emergency use, PowerFlares are used for HAZMAT spills. They are waterproof and float and can be run over by any vehicle. Operational: 8 to 150 hours, based on which of 10 flash patterns is being used. Replaceable CR123 battery. Rechargeable version also. Several LED colors available. Weighs 7 ounces, about the size of a hockey puck.