Garmin Varia RTL515 Radar Tail Light Review
A rear light with radar that warns of cars approaching from behind. On gravel routes with road links it is the most practical safety addition on the market.
The verdictThe most useful safety addition for a gravel rider whose route uses fast roads. Expensive, and pointless on traffic-free trails.
The Varia RTL515 detects vehicles from 140 metres behind you and flashes a warning on your paired Garmin Edge or smartphone. The psychological effect is hard to overstate: on a fast descent on a narrow lane, knowing a car is approaching 8 seconds before it reaches you gives you time to move right, signal, or slow down. The radar icon on the Edge display shows each approaching vehicle as a bar that gets taller as the car closes the gap, making the speed and proximity of traffic immediately readable without looking backwards.
The tail light itself is IPX7 waterproof and visible for up to 1 mile in daylight flash mode, which is the priority setting for road use. Garmin's manual gives about 16 hours in day flash and 6 hours in solid or night flash, with radar running, so night riding needs a charge every day. It mounts cleanly on a round or aero seatpost using a standard Garmin quarter-turn mount, and at about 71 g it adds little to a loaded bike. Compatible with ANT+ head units and the Varia smartphone app if you don't run a Garmin computer.
What works
- 140m vehicle detection range
- Native Garmin Edge integration
- IPX7 waterproof
What doesn't
- 6 h in night modes, daily charging
- Requires compatible head unit or phone for alerts
- Mount not ideal for aero seatposts
Buy it if
Gravel riders whose routes link through fast rural roads, especially those already using a Garmin or compatible head unit
Skip it if
You ride traffic-free trails, or need a rear light that runs all night without a charge
Others we scored in this category
One email when something changes
We re-check prices and picks quarterly. When a recommendation changes — or a product we rated well turns out not to last — you hear about it. No weekly digest, no gear-of-the-day.
By subscribing you agree we can email you when a recommendation changes. That is the only thing we use your address for. Unsubscribe in one click; we don't sell or share the list — see our privacy policy.