Ronhill Bright LED Red Light Shoe Clip for running & cycling is lightweight, compact, durable and shock resistant. The ultra bright LED can be set on flash or permanent glow and is easy to turn on/off. The batteries last for 70 hours on permanent or 100 hours on flash and are easy to change. This weather proof road safety device is lightweight at only 30 gms ( 1.05 oz ). Batteries included.