Specifications: This LED wheel light can make your riding visible and safer at night. Water-resistant design to ensure light work normal in the rainy days. Small size battery box powered by one AA battery which is easy to install and remove. A pretty cool cycling wheel light for riders. Features: Super bright 2.2m LED light string, contains 20 LEDs. Can be fixed on any cycle with standard spoke with diameter no more than 2.3mm. ON/OFF button to switch on/off the light and change between two light modes (steady or flash). Powered by one AA battery (not included), continuously flash time up to 20 hours. Water resistant design, can be used in rainy days. No tools required, fast and easy installation. Make your riding safe and visible at night. Type: LED Light String Material: ABS LED Quantity: 20 LED Lights Power Supply: 1 x AA Battery (Not Included) Working Hour: 13-15 Hours Light String Length: 2.2m/86.61" (Approx.) Battery Box Size: 6.5cm x 3cm x 2.2cm/2.56" x 1.18" x 0.87" (Approx.) Installation: 1. Put screw stem implant into cycle spoke. 2. Screw cap tightly. 3. Twine the thick wire on latest spoke tightly. 4. Enlace the light string on spoke following. Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x LED Light String