Planet Bike Superflash USB Taillight. Features: USB rechargeable lithium ion battery for 36 hours of runtime from a 2-4 hour charge 1/2 watt Power LED plus 2 eXtreme LEDs for visibility up to 1 mile Steady and attention-grabbing Superflash flashing mode Highly visible, even in daylight Ultra compact vertical design is weatherproof, lightweight and durable Includes bike mounts and clip mount for multiple mounting options Soft touch button has affirmative feel, even with gloves on Specs: Model Package:rear Runtime:36 hrs Color:red/black Weight:n/a