[Programmable App Controlled, Easy to Use]: Our 4-in-1 helmet taillights can be controlled by mobile phone app to improve the convenience and safety of riding. You can easily adjust the modes like brightness, turn-signals, brake light etc, through the programmable app to adapt to different environments and needs. Provides more control and personalised choices for more peace of mind and enjoyment of your ride! [Riding mode Intelligent Auto-Sensor]: The AUTO mode needs to be enabled on the app. Real-time changes in the riding speed and direction are obtained through the phone App and the effect is displayed on the helmet light. When you ride, it display "GO" and when you stop, it prominently display "STOP". This intelligent interactive design not only enhances cycling safety, but also brings convenience and comfort to cyclists. [HD Display & Waterproof]: This helmet taillight is made of ABS with excellent waterproof function. USB Type-C charging for 4 hours, can be used for 10 hours. There are 576 PCS light beads and 2020 RGB LED beads with adjustable brightness, suitable for night riding. [Personalised DIY Function]: Our helmet light has some preset patterns choose from, or can be DIY graffiti animation, text and full color according to personal preferences and needs. You can also upload your own material, it's really ! This item match most Motorcycle helmets curvatures, but be noted the size of the mount is not suitable for some bicycle helmets. [Ideal Gift]: 4-in-1 Helmet light with taillight turn-signals speedometer and programmable app, which can be given as a gift to outdoor motorcycle or cycling enthusiasts. Colour:As Shown Material:Plastic Package Contents: 1 * LED Helmet Taillight Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.