Make sure you're highly visible on all of your long, strange trips via bike courtesy of the Planet Bike Grateful Red Tail Light. This LED tail light is supremely bright, features three convenient light modes, and can run up to 150 hours on 2 AAA batteries. Additionally, it's plenty light (85 grams) and completely weatherproof for the ultimate in reliability. PB power array and reflector provide visibility up to 1 mile Three modes: Steady, Superflash, and Courtesy Flash Ultra-compact case is weatherproof, lightweight, and durable Up to 150 hours of run time via 2 AAA batteries (included) Includes rear rack and seatpost mounts Weight: 85 grams