Varia RTL515 rearview radar provides visual and audible alerts for vehicles approaching from behind up to 153 yards (140 meters) away. This radar works seamlessly with your Edge bike computer or compatible smartphone as well as select Garmin wearables or the optional radar display unit. This smartphone app helps you increase your awareness by providing graphics — plus tone and vibration alerts — that indicate the position and speed of approaching cars. When used with a compatible smartphone, Varia radar integrates with your favorite apps, such as Ride with GPS, to overlay your maps with rearview radar alerts. Alert motorists to your presence as soon as possible with daylight visibility up to 1 mile. Easily mount this sleek, compact device on the seatpost of almost any road-use bicycle. The vertical design allows for better leg clearance and a perfectly comfortable ride. Varia RTL515 features multiple modes, including peloton mode, which provides a low-intensity flash that is kind to other cyclists’ eyes when riding in a group. Time spent charging is not as good as time spent riding. Get up to 16 hours of battery life in day flash mode and up to 6 hours in solid mode.