LED Flashing Armband: increasing visibility and safety during early morning night sports and outdoor activities. You can be seen in the dark when running, cycling, walking dog, camping etc. Total length: 35cm. Fits size from 28 to 32cm, suitable for men, women and children, by simply wrap it to wrist, ankle, arm and leg, or tied on bike, helmet, schoolbag, backpack, anywhere you prefer. Replaceable batteries: each armband comes with 2 batteries, can work about 60-80 hours. When battery runs out , you can simply replace it with new CR2023 batteries. 4 Models: fast flashing, slow flashing, continuous bright and off. Package included: 4 * Armbands with LED flashing light (equipped with batteries) Colour:Armbands Green (4-Pack) Total Length: 35cm Adjustable Length: 28-32cm Colors Available: Green Material: Nylon Webbing + Reflective tape + LED Lighting Strap 4 Models: fast flashing, slow flashing, continuous bright and off Battery Requirements: 2 x CR2032 button battery per armband (included) Battery Life: normally 60-80 hours, battery can be replaced