According to some embodiments, a flasher 101 to be mounted on a rear portion of a straddle type vehicle includes a lens 120, a cover 160 mated with the lens 120, and a leg 180 connecting the cover 160 with a vehicle body. A mating face of the cover 160 and the lens 120 is slanted with respect to a direction in which the leg 180 extends. The lens 120 is shorter in a vehicle widthwise direction than in a vehicle lengthwise direction.