* See and be seen with Varia RTL515 rearview radar with tail light. * It pairs with your Edge bike computer, other Garmin device or compatible smartphone to alert you of vehicles approaching from behind up to 153 yards (140 meters) away. * When used with your compatible smartphone, the Varia app helps increase your awareness with vibration alerts and more. * With daylight visibility up to 1 mile, motorists will be able to see you from a distance. * The radars compact vertical design allows for device mounting on most road-use bicycles.* Peloton mode provides a low-intensity flash that is kind to other riders eyes when riding in a group.