XuanWheel Customizable Bike wheel LED Display, Rechargeable Bicycle Wheel Light, Waterproof Intelligent 96 RGB Colorful LED Spoke Lights XuanWheel S1, a PROGRAMMABLE bicycle light that can turn your bicycle wheel into a colorful screen. The light shines both sides, and is controlled via APP. Search "xuanwheel" APP in google play or apple store, then download a galaxy of pictures! Also, you can upload your own pictures, video, GIFs, DIY your own text---Never be fixed to pre-stored pics any more! The only limitation is your imagination. Click the button on APP to shift from front wheel to back wheel, you can have A PAIR of spokes lighting your bike simultaneously. The APP monitors your riding speed, maximum speed and records your journey time and mileage. Just leave these mess calculations to XuanWheel, and be a happy, free night rider. It consists of 96 ultra-bright RGB LEDs, the bright light ensures your bike visible in dark light. 1300 mah built-in rechargeable battery, keeping power on for 9-20 hours when fully charged. Easy mounting, and waterproof in all weather conditions. It displays clearest image in a speed of 16km/h-60km/h, no problem even when you are riding slowly. Fits 26 inches bike wheel and above sizes. Both android and ios system applicable. Installation tutorial available. Most importantly, price reasonable and affordable--- YES, we believe everyone deserves this joy. Note: Support Bluetooth 4.0, support Android 4.3 and above, iPhone 7 and above system. This unit only has ONE spoke light inside, and XuanWheel S1 only has ONE arm compared to XuanWheel X1.It requires higher riding speed than XuanWheel X1, and 16km/h-60km/h is the best range for clear display.