Nite Ize LED Helmet Marker. Be Seen! Be Safe! This flexible LED Helmet Marker is great for bicyclists, and other outdoor enthusiasts who are conscious of their safety. Flexible, rugged design - shock resistant. Reflective when turned off. 150 hour battery life, 100,000 hour LED life. Push button switch has 3 modes: 1 - flash, 2 - glow, 3 - off. Easy to replace battery included. Hook and Loop fastener (like Velcro®) allows easy removal and replacement of Helmet Marker