The led armband increases visibility during night sports. Two light modes: steady on and flashing. Can be seen by car after dark when running, bicycling or just walking with the dog. Keep you safe when performing outdoor activities. Durable and elastic band encases a flexible LED core. It is easy to adjust for a loose or snug fit so you can be conformable when you run. Battery life is up to 60 hours, ideal for sport, cycling, walking, Jogging, running, marathon and low-light environments.