B & M Topfire cycle helmet LightsTopfire Cycle Helmet LightsInnovative and stylish cycling helmet light solution. Four very bright red flashing LED lights attached in rear air vents of your bike helmet. The thin, flat cables can be easily routed to the chin strap via the inner helmet surface to connect to the flat, round cell housing with on/off button that is attached by clips or adhesive pads. Please ensure that the helmet is clean and dry before attaching the LEDs into the air vents.Total weight including battery 18 grams. LEDs attached in rear air vents using sticky pads. 100 hours plus run time. Easy to replace standard 2032 battery.