The latest bike taillights have two high-brightness imported LED red lights and two blue lights working. The first red and blue lights are on at the same time, and the second two red lights and two blue lights are flashing at the same time, which can be seen from 5 kilometers away. Three stops and two red lights go on, four red lights and blue lights flash at the same time, and five red lights and international flashing lights. Six. Lighting with 2 AAA batteries.