Features: USB Rechargeable and Long-lasting: The reflective running armband is available in USB rechargeable/battery models for easy charging from your computer mobile power or any USB port or a battery model that does not require charging. Optimal Visibility: Featuring high visibility reflective optical fiber our light-up bands provide maximum visibility keeping you safe and visible even in low light conditions. Dual Light Modes: Switch between flashing and normal light modes allowing you to customize your visibility based on your preference and needs. Stylish and Comfortable: LED armbands with adjustable hook and loop not only provide safety but also add a touch of style to your outdoor gear. The adjustable wristband ensures a comfortable fit for all users. Multi-purpose Usage: Whether you're cycling walking or engaging in other outdoor sports our armbands provide the safety and visibility you need for a worry-free experience. Specifications: Material: Nylon Model: Battery/Charging Length: 29cm Weight: Charging Model:47g BatteryModel:30g includes: Choice 1-4: 1 * Reflective running armband 2* Batteries Or Choice 5-9: 1 * Reflective running armband with 2*Batteries 1 *Charging cable