Rubber Sleeve Suitable for Varia RTL515, Cycling Rearview Radar with Tail Light, Visual and Audible Alerts for Vehicles Up to 153 Yards Away Rearview radar with tail light provides awareness of vehicles approaching from behind up to 153 yards (140 meters) away Pairs seamlessly with your Edge bike computer and compatible smartphone as well as select Garmin wearables or the radar display unit When used with your compatible smartphone, the app provides graphics plus tone and vibration alerts that indicate approaching cars When used with a compatible smartphone, radar integrates with third-party apps such as Ride with GPS to overlay your maps with rearview radar alerts Daylight visibility up to 1 mile alerts motorists to your presence as soon as possible Compact vertical design mounts easily to most road-use bicycles Note: The data are all measured manually; please allow 1–3 cm error. Due to differences in light and display, there may be some color variation. The actual product received shall prevail.