This 9 LED lights reflector triangle serves as a roadside warning safety sign. Use as a caution sign to other drivers if you are ever on the side of the road fixing an unfortunate auto problem, like engine trouble or a flat tire. Bright yellow triangle has flashing bright red lights that are very noticeable. Magnetic base allows you more placement options. Cuation triangle comes in 3 modes: on, flashing, or off. Triangle also folds making it easy to store. Needs 3 x AAA batteries, NOT included.