Garmin Varia RearVue 820

The Garmin Varia RearVue 820 represents the next generation of cycling safety, featuring Garmin's most powerful and precise rearview radar system to date. Engineered with a significantly wider 60° radar beam width, it tracks overtaking vehicles from up to 175 metres away, providing real-time data on vehicle size, closing speed, threat level, and lateral lane positioning. The integrated high-output intelligent tail light provides up to 2 km of daytime visibility and features an automated, deceleration-sensing brake light to alert motorists when you are slowing or stopping. With comprehensive ANT+ and Bluetooth connectivity alongside a rugged IPX7 waterproof rating, it integrates flawlessly with cycling computers, smartwatches, and smartphones to bring elite situational awareness to every ride.

Specifications

Radar & Detection Capabilities

• Maximum Detection Range: Tracks approaching vehicles up to 175 metres away.

• Radar Beam Width: Ultrawide 60° field of view for exceptional coverage on twisting roads, junctions, and wide lanes.

• Intelligent Tracking Metrics:

  • Vehicle Size Classification: Categorizes and displays the size profile of approaching vehicles on compatible head units.

  • Lateral Vehicle Positioning: Visualizes exactly where the overtaking vehicle is positioned within the lane relative to the rider.

  • Vehicle Threat Classification: Dynamic speed-, size-, and lateral range-based calculations color-code the severity of approaching threats.

  • Relative Speed Alerts: Retains consistent tracking and visibility alerts even for vehicles matching the cyclist's exact traveling speed.

Smart Lighting Modes & Lumens

• Day Flash Mode: 100 Lumens of high-intensity visibility (visible up to 2 km / 1.24 miles away).

• Night Flash Mode: 40 Lumens optimized for low-light conditions.

• Solid Mode: 25 Lumens for steady, high-visibility output.

• Peloton Mode: 8 Lumens dimmed output, optimized to protect the vision of fellow riders when traveling in close group pacelines.

• Smart Brake Light: Automated structural feature that flashes or brightens dynamically to alert following motorists the moment you decelerate or stop.

• Custom Configuration: Fully customizable light mode profiles manageable via the Varia Mobile App.

Battery Life Matrix

The Varia RearVue 820 features highly optimized power management profiles based on active output modes:

Connectivity & Hardware Integration

• Dual-Band Wireless: Equipped with full ANT+ and Bluetooth Low Energy (BLE) architecture to transmit radar data and light control commands simultaneously.

• Ecosystem Compatibility: Seamless native integration with Garmin Edge cycling computers, compatible Garmin smartwatches, dedicated radar display units, and the standalone smartphone-based Varia mobile app.

Physical Profile & Durability

• Dimensions: 98.9 x 25.9 x 43.2 mm (3.9" x 1" x 1.7")

• Weight: Lightweight 90 g (3.2 oz) chassis.

• Waterproof Rating: Fully IPX7 certified (withstands incidental exposure to water of up to 1 metre depth for up to 30 minutes; completely weather-sealed against heavy rain and road spray).

• Viewing Angle: 220° peripheral lighting coverage pattern to optimize side-on visibility at intersections.

Technical & Security Lifecycle

️ Manufacturer Security Guarantee: Garmin officially guarantees dedicated software security updates and firmware patch maintenance for the Varia RearVue 820 hardware system until at least 30 December 2027.