Safe Riding Warning light, turn light: The well-positioned LED warning light warns other traffic to give you enough riding space. The turn light indicates left or right turns more clearly to ensure safety. SOS: In the case of an accident, the bump will trigger the sensor on the helmet. After 90 seconds, LIVALL Riding APP will automatically send an SOS message with your location to the preset contact. Easy Communication One Key to Answer: One Key to Answer makes it very convenient to answer calls without stopping riding, so you needn't worry about missing important calls. The high-quality windproof microphone is designed to have a special sound volume and sound wave control feature, enabling youto clearly hear the caller without affecting others and protecting your privacy. Walkie-talkie: With the LIVALL Riding App, you can use the walkie-talkie function to communicate with your riding mates in both one-to-one and group talks wherever you are. (This function requires a mobile network and incurs a small data fee.) Pleasure Riding Bluetooth speaker: The best sports headphones for you to wear to listen to music when riding blocks out some outisde sounds. The bluetooth speaker in LIVALL's smart helmets enables you to enjoy great tunes without affecting others. The design of the special sound volume and sound wave control in the Bluetooth speaker ensures sound doesn't travel far. Low wind drag: The unique design with holes on the body combines with the form factor's aerodynamics so wind passes through the gap between the head and helmet, minimizing wind drag. Professional Skill Professional cadence sensor: The national patented mini cadence sensor provides various installation modes. By connecting the cadence sensor to the LIVALL Riding App through Bluetooth, you can acquire your riding records anytime. App records: The mileage, time, instant speed, average speed, and accumulated riding statistics are available on the app (requires GPS).