Review on 🚴 Garmin Varia RTL515 Cycling Rearview Radar with Tail Light | Visual & Audible Alerts Up to 153 Yards | 010-02376-00 (One Size) by David West

For roads with little traffic (country gravel in my case) the thing is fantastic and I would not do without it, either alone or in a group. Pair it to your main GPS device like any other sensor (power meter, cadence sensor, etc.) and it works like magic. Because it supports ANT+ (and Bluetooth), your cycling friends can connect to Varia via ANT+ (as opposed to Bluetooth) at the same time. In this case, everyone gets notifications at the same time - of course, your friends need to be within range, and everything is relative to your location, but this thing catches vehicles over 100m away, so who cares about a few meters. Included mounts with a typical Garmin rubber strap mount are acceptable, but for round seatposts the aftermarket Garmin fixed mount is much more secure and worth it in my opinion. With curved poles you are more limited on placement as the angle of the mount is fixed relative to the horizon (Garmin please make it adjustable as a lightweight mount). I have it on two of those curved posts and it works fine - I just have to adjust it below the point where the seatpost starts to flex or the radar will point way down and it won't work. The rush of the wind, chatting with friends, the sound of gravel all prevent you from hearing a car approaching from behind, but this little guy is always on the lookout for you and eliminates surprises. Several vehicles can also be recorded at the same time. If your buddies come in from behind a little faster - I'm guessing an approach speed of about 3 miles per hour or so - the radar will give a false alarm. A few false positives don't detract from how great it is. Maybe this is something that can be tweaked via firmware, but I'd rather maximize sensitivity and deal with a few unnecessary warnings.