Material: plasticSize:6*4*1cmPower: 3x AG10 button batteries (built-in)Color:Pink Blue Green BlueFeatures:1. Universal fitment and easy to install no special wires can be easily installed and removed.2. Fits most valves of road mountain bicycles..3. Bright led will turn on while the vehicle is moving and off when stop.4. Silver body with ultra bright long life-span led lights.5. Lights increase night-time and bad weather visibility for safety.Note:The battery needs to be positive pole downward(with the word side is positive).Fit for US and UK valveinstall to French Valve need with adapter.Before install need to remove the inside of the insulating paper. And DO NOT remove the transparent plastic of the lamp housingor it will cause the battery discharge heat and short circuit.Package includes: 4pcs x Bicycle Wheel Lights 50x button batteries.