Allows visual communication with other riders. Three-position waterproof toggle for selecting green, yellow or flashing yellow indicators. LED indicators show when riders are approaching, when another rider needs assistance and when you’re the last rider in a group. 18 yellow and 9 green LEDs. Connects to 12VDC or 12VAC power source. Includes standard cradle mount with 3M? adhesive and in-line quick disconnect. 9V battery backup. Dimensions with cradle mount; 3.75″ L x 2.75″ W x 1.5″ H.