Living Depot Led Armband Running Safety Cycling Jogging Reflective Belt Wrist/Ankle Runners Lights are great for jogging, dog walking, running safety and personal safety. The Led Armband can also be used for kids night safety, marathon races; with many other uses. Transportation Light Up Armbands Emergency Roadway Lights The length is 10 - 13 inches battery included to last an average of 100 hours. Perfect for cancer awareness running or jogging events and other fundraiser or fundraising ideas. 2 LED light modes:1. blinking 2.blinking fast 3. full illumination settings. easy to use