Garmin Varia Rearview Radar Tail Light The tail light brightens and blinks when approaching vehicles are detected for an extra measure of safety Detects approaching vehicles from up to 140 meters Compatibility for the Edge 1000, Edge 810, Edge 520, Edge 510 and Edge Touring Plus Includes: Varia radar tail light transmitter (RTL 500), seat-post quarter-turn mount, universal seat-post quarter-turn mount, microUSB cable, manuals