Road Genie Red LED Tow Lights - DOT Approved - Magnetic - TA1872LED-DTThis set of lights will enable you to tow another vehicle safely by providing warning lights on the back of the vehicle. They serve as a way of warning other motorists that the vehicle is being towed, and allow other drivers to maintain proper stopping distance. This unit is powered by your vehicles accessory outlet (cigarette lighter). Provides 100,000 hours of light! Each light is 4 inches in diameter, and each unit with magnetic base is 7 inches