Garmin Varia RearVue 820 Radar Tail Light, Model 010-03180-00

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Product guide

Garmin Varia RearVue 820 Radar Tail Light, Model 010-03180-00

Model: Garmin Varia RearVue 820 combines a rearview radar with a tail light for cyclists who want vehicle alerts and rear visibility from one seatpost-mounted unit. Alerts appear through the Varia smartphone app or compatible Garmin devices, while claimed battery life varies by operating mode.

At a glance

Radar alerts can be shown and heard on the Varia app, compatible Edge cycling computers or selected Garmin smartwatches.
The listing claims visibility from up to 2 km (1.24 miles) and a distinct brake-light flash when slowing or stopping.
Day flash, night flash, solid and lower-intensity peloton modes are listed, with custom patterns available in the app.
Radar is described as tracking vehicle size, movement and threat level, including same-speed following in suitable conditions.

Price

$249.99Save 17%

Reference price: ~~$299.99~~

Price checked: Nov 14, 2026

View offer

Often bought together

Garmin Edge® 1050, Premium Cycling Computer | Large & Vivid Touchscreen, Advanced Cycling Metrics, Built-In Speaker, Garmin Coach, Groupride, Road Hazard Alerts

$599.98

Garmin Varia Radar Seat Rail Mount

$46.99

Pros and cons

Pros

Combines rear vehicle radar alerts and a tail light in one seatpost-mounted unit.
Multiple light patterns include a lower-intensity peloton mode and app-created patterns.
The listing specifies different battery-life claims for day flash and radar-only operation rather than a single runtime.

Cons

The 30-hour figure applies to radar-only operation, not the tail light's day-flash mode.
The seat rail mount kit is sold separately, so this setup is limited to the listed seatpost mount unless another mount is obtained.

Technical specifications

13 specifications

Identity
Brand	Garmin
Model	010-03180-00

Power and battery
Power configuration	Battery Powered
Battery life, day flash mode	up to 24 hours
Battery life, radar-only mode	up to 30 hours

Dimensions and installation
Mounting type listed	Seatpost Mount
Dimensions listed	1.7"L x 3.9"W x 1"H
Weight listed	3.2 ounces

Materials and protection
Material listed	Plastic
Color	Black
Ingress protection rating listed	IPX7

Radar and lighting
Visibility distance claimed	up to 2 km (1.24 miles)
Light patterns	day flash, night flash, solid mode and peloton mode

What to know before buying

Radar alerts require a compatible Edge cycling computer, selected Garmin smartwatch or the Varia smartphone app. Same-speed tracking may be unavailable at slower speeds or when weather or obstructions block the radar's view. Battery claims are up to 24 hours in day flash mode and up to 30 hours in radar-only mode. The seat rail mount kit is sold separately.

What’s in the box

Included

Varia RearVue 820 radar tail light
Mounting kit
Charging cable
Documentation

Who is it for?

A good fit for

Cyclists wanting rear-approach alerts alongside a rear light and who can use the Varia app or a compatible Garmin device.
Riders seeking brake-light signaling and several lighting patterns, including a lower-intensity option for group rides.

Less suited to

Riders seeking a light-only device without radar features or those who need radar alerts without a compatible display or smartphone app.
Buyers who need a seat rail mount included in the package.

Garmin Varia RearVue 820 Radar Tail Light, Model 010-03180-00 · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.3 / 5 · 141 ratings

5 stars74%74%
4 stars7%7%
3 stars6%6%
2 stars3%3%
1 star10%10%

Customer feedback highlights radar detection, visibility, brightness and battery life as strengths. Reported mixed experiences concern reliability, price and connectivity, including a compatibility issue with a Garmin 840 computer. These perceptions matter because the unit's radar alerts depend on a compatible display or the Varia app, while its claimed battery life varies by mode. Aggregate ratings are generally positive but include a notable one-star portion, so they do not establish consistent performance for every setup.

Positive themes

Customers praise the radar function, visibility, brightness and battery life. One reported comparison says vehicles were detected farther back than with previous models.

Negative themes

Some customers report technical issues and question the price.

Mixed feedback

Reliability and connectivity feedback is mixed. A customer reported compatibility trouble with a Garmin 840 cycling computer.

Frequently asked questions

How are radar alerts displayed?

The listing says alerts can be delivered through the Varia app on a smartphone, compatible Edge cycling computers or selected Garmin smartwatches. Confirm compatibility with your particular device before buying.

How long does the battery last?

The listed maximums are up to 24 hours in day flash mode and up to 30 hours in radar-only mode. The radar-only figure does not describe runtime with the light operating.

Can it track vehicles moving at the same speed?

The listing describes same-speed tracking but says it may be unavailable at slower speeds or when weather or obstructions prevent the radar from detecting the road.

Is a seat rail mount included?

The listed included components are a mounting kit, charging cable and documentation with the radar tail light. The seat rail mount kit is identified separately as sold separately.