Garmin Varia Rearview 820

Battery life: 10 hours solid, 15 hours peloton, 10 hours night flash, 24 hours day flash, 30 hours radar-only. With our most powerful and precise radar tracking technology, Varia RearVue 820 radar detects vehicles approaching from up to 175 meters (191 yards) away with a wider field of view. Our brightest tail light means you’ll be visible from up to 2 km (1.24 miles) away. A brake light detects when you’re slowing or stopping and displays a unique flash pattern. See alerts for small, medium and large vehicles, and see when a vehicle changes lanes, along with its threat level — when riding with the latest compatible Edge® cycling computers or the Varia app on your smartphone. For visual and audible alerts while you ride, connect this radar to the Varia smartphone app, select Garmin smartwatches or compatible Edge cycling computers. Ride with four different light patterns: day flash, night flash, solid mode and peloton mode, which helps preserve the eyes of riders behind you. Create your own custom light patterns in the Varia app on your smartphone. A sleek, compact design and new seatpost mount means Varia RearVue 820 fits cleanly onto almost any road or gravel bicycle and is compatible with the Varia seat rail mount kit (sold separately).