| Manufacturer | Garmin |
|---|---|
| Type | Rearview bike radar, with a tail light on all but the RVR315 and a camera on the RCT715 |
| Series | Varia |
| Released | Varia RTL515 and RVR315 13 May 2020; Varia RCT715 18 May 2022; Varia RearVue 820 3 February 2026 |
| Price | Garmin UK sells the RearVue 820 at £259.99, the RCT715 at £299.99, the RTL515 at £169.99 and the RVR315 at £129.99. US prices at launch were $299.99 for the RearVue 820 and $399.99 for the RCT715. |
| Predecessor | Varia RTL510 (for the RTL515) |
| Successor | The RearVue 820 replaces the RTL515 as Garmin’s main radar tail light |
| Variants | Varia RearVue 820; Varia RCT715 with a 1080p camera; Varia RTL515; Varia RVR315, radar only with no light |
| Part numbers | RearVue 820 010-03180-00; RCT715 010-02476-00; RTL515 010-02377-01; RVR315 010-02254-00 |
Specifications as listed by Garmin. Features reflect the latest Garmin software.
Expert opinion | Which Varia radar | Features | Specifications | Battery life | Quick answers | Further reading
Expert opinion
Who it suits: Road cyclists and commuters who ride in traffic and want early warning of vehicles coming up from behind.
The RearVue 820 is the one to buy. It sees vehicles from 175 metres across a 60° arc, shows their size and lane changes on a compatible Edge or the Varia app, adds a brake light, and lasts up to 24 hours in day flash. The RTL515 does the basic job with a 140-metre range and up to 16 hours in day flash.
The RCT715 adds a 1080p camera that locks footage after an incident, but recording cuts battery to between four and six hours, and its radar is the older design. The RVR315 is radar only, for riders who already have a rear light they like.
Garmin Varia RearVue 820
See cars coming from 175 metres behind, with a brake light and up to 24 hours of battery.
Garmin Varia RCT715
Rear radar and tail light with a camera that saves the footage if something happens.
Which Varia radar
All four warn you of vehicles coming up from behind and show them on a compatible Edge bike computer, Garmin watch or the Varia app on your phone. The RearVue 820 is the newest and the one to buy for radar alone. It sees cars from 175 metres instead of 140, covers a 60° arc instead of 40°, shows the size of each vehicle and when it changes lane, adds a brake light, and lasts up to 24 hours in day flash. The RCT715 is the only one with a camera. It records 1080p video behind you and locks the footage if it detects an incident, but the camera cuts battery life to between four and six hours. The RTL515 is the older radar tail light, and the RVR315 is the same radar with no light, for riders who already run a separate rear light; it is the smallest at 51g and lasts seven hours. Garmin lists security updates for the RCT715, RTL515 and RVR315 that have already ended, while the RearVue 820 is covered until at least 3 February 2028.
Features
Radar
- Visual and audible alerts for vehicles approaching from behind
- Threat level based on vehicle speed, and on the RearVue 820 also size and lane position
- Same-speed vehicle tracking on the RearVue 820
- Alerts on Edge bike computers, selected Garmin watches with haptic or voice alerts, and the Varia app
- Works with third-party apps such as Ride with GPS on your phone
Lights
- Day flash visible up to 1.6 km, or 2 km on the RearVue 820
- Solid, peloton, night flash and day flash modes
- Peloton mode uses a low-intensity flash that will not dazzle riders behind
- Brake light and custom light patterns on the RearVue 820
- Radar-only mode to save battery
Camera (RCT715 only)
- Continuous 1080p or 720p recording at 30 frames per second
- Saves footage from before, during and after a detected incident
- Camera control from an Edge, a Garmin watch or the Varia app
- 16GB memory card included
- Data overlay can show the speed of approaching vehicles
Specifications
| Specification | Varia RearVue 820 | Varia RCT715 | Varia RTL515 | Varia RVR315 |
|---|---|---|---|---|
| General | ||||
| ANT+ | Yes (radar, bike lights) | Yes (radar, bike lights) | Yes (radar, bike lights) | Yes (radar) |
| Dimension | 98.9 x 25.9 x 43.2 mm (3.9″ x 1″ x 1.7″) | 106.5 x 42.0 x 31.9 mm (4.2″ x 1.7″ x 1.3″) | 98.6 x 19.7 x 39.6 mm (3.9″ x 0.8″ x 1.6″) | 40 x 72 x 20 mm (1.8″ x 2.8″ x 0.8″) |
| Weight | 90 g (3.2 oz) | 147.0 g (5.2 oz) | 71.0 g (2.5 oz) | 51.0 g (1.8 oz) |
| Light modes | Solid, peloton, night flash, day flash | Solid, peloton, night flash, day flash | Solid, peloton, night flash, day flash | Not listed |
| Custom light mode configuration | Yes (with Varia Mobile App) | Not listed | Not listed | Not listed |
| Radar-only mode | Yes | Yes | Yes | Not listed |
| Lumens | 25 solid, 8 peloton, 40 night flash, 100 day flash | 20 solid, 8 peloton, 21 night flash, 65 day flash | 20 solid, 8 peloton, 29 night flash, 65 day flash | Not listed |
| Water rating | IPX7 | |||
| BLE | Yes (radar, bike lights) | Yes (radar, camera control) | Yes (radar) | Yes (radar) |
| Viewing angle | 220° | 220° | 220° | Not listed |
| Visibility distance | 2 km | 1.6 km (1 mile) | 1.6 km (1 mile) | Not listed |
| Rear tail light | Yes | Yes | Yes | Not listed |
| Brake light | Yes | Not listed | Not listed | Not listed |
| Rear radar | Yes | |||
| Lateral vehicle positioning | Yes | Not listed | Not listed | Not listed |
| Vehicle size classification | Yes | Not listed | Not listed | Not listed |
| Vehicle threat classification | Speed-, size- and lateral range-based | Speed-based | Speed-based | Not listed |
| Maximum vehicle detection range | 175 m | 140 m | 140 m | Not listed |
| Radar beam width | 60° | 40° | 40° | 40° |
| Wi-Fi | Not listed | Yes | Not listed | Not listed |
| Integrated camera | Not listed | Yes | Not listed | Not listed |
| © the5krunner. Link required. | ||||
| Connectivity | ||||
| Varia app compatibility | Yes | Radar display, camera control and video transfer | Yes | Yes |
| Security updates | ||||
| Security updates until at least | 3 February 2028 | 18 May 2024 | 13 May 2022 | 13 May 2022 |
| © the5krunner. Link required. | ||||
| Storage | ||||
| Accepts Data Cards | Not listed | 16 GB card included | Not listed | Not listed |
| Camera (RCT715) | ||||
| Camera modes | Not listed | Continuous, off, radar-activated | Not listed | Not listed |
| Camera settings | Not listed | 1080p/720p, with 30 FPS | Not listed | Not listed |
| Accelerometer | Not listed | Autolock footage upon incident detection | Not listed | Not listed |
| Camera control | Not listed | Garmin Edge bike computers, selected Garmin smartwatches and Varia app | Not listed | Not listed |
| © the5krunner. Link required. | ||||
Battery life
| Model | Garmin’s battery life rating |
|---|---|
| Varia RearVue 820 | 10 hours solid; 15 hours peloton; 10 hours night flash; 24 hours day flash; 30 hours radar-only |
| Varia RCT715 | 4 hours solid or night flash; 5 hours peloton; 6 hours day flash (all with 1080p recording) |
| Varia RTL515 | 6 hours solid; 8 hours peloton; 6 hours night flash; 16 hours day flash |
| Varia RVR315 | 7 hours |
| © the5krunner. Link required. | |
Garmin Varia RearVue 820
See cars coming from 175 metres behind, with a brake light and up to 24 hours of battery.
Quick answers
Which Garmin Varia radar should I buy?
The RearVue 820 for most riders, because it has the longest range, the widest view, a brake light and the longest battery life. Buy the RCT715 only if you want a rear camera in the same unit.
What is the difference between the Varia RearVue 820 and RTL515?
The RearVue 820 detects vehicles from 175 metres against 140, covers 60° against 40°, shows vehicle size and lane changes, adds a brake light and lasts up to 24 hours in day flash against 16.
Which Varia radar has no light?
The Varia RVR315. It is radar only, weighs 51g, lasts up to seven hours and costs £129.99 at Garmin UK, so it suits riders who already use a separate rear light.
Does the Varia radar work without a Garmin Edge?
Yes. It works with the free Varia app on your phone and with selected Garmin watches, which can give haptic or voice alerts.
How long does the Varia RCT715 battery last?
Garmin rates it for four hours in solid or night flash, five hours in peloton mode and six hours in day flash, all while recording 1080p video.
Further reading
- Garmin Varia RearVue 820: all you need to know
- Varia flash pattern ban in the EU
- Bike computers compared
- Garmin hub
- Garmin watch and device specifications
- Release Radar
Related devices
Front camera and headlight: Garmin Varia Vue, a 600-lumen headlight with a 4K camera that records alongside the RCT715.
Bike computers to pair with: Garmin Edge 1060, Edge 1050 and Edge 850 show radar alerts and camera controls alongside your ride data.
Small things I always use
- Garmin 90-degree charging adapter: Charges your Garmin from any USB-C cable. Essential when travelling. I use one.
- Body Glide: The blue anti-chafe stick swimmers and runners carry. I use it.
- Speedo earplugs: Fewer ear infections and no cold-water dizziness. I use them.
- Dryrobe Advance: My winter changing robe for open-water swims. I use one. A cheaper option is the AONYIYI changing robe.
- Maurten: Race fuel that stays easy on the stomach. I use them.
- Beet It Sport nitrate shots: Beetroot shots I take in the days before a race. I use them.
- Garmin charging puck: The quickest way to top up before a session. I use one.
- Injinji: Toe socks that stop rubbing, so you run more. I use them.
- Ultimate toe protectors: Stop black toenails on long runs. They work. I use them.
- Compressport R2 v2 calf sleeves: My calf sleeves of choice. I use them.
- Cellucor C4: My pre-workout before hard sessions.
- TPU tubes: Schwalbe Aerothan, Tubolito and Pirelli SmarTube. Light, tiny spares. I use all three.
- G8 insoles: Adjustable insoles that are good. I use them.
- Cycplus Cube: A 97g electric pump that gets a road tyre rideable in two minutes. I carry one. 5% off with code THE5KRUNNER.
Watches and sensors
- Polar H10: My daily driver for waking HRV.
- Polar Verity Sense: My backup arm-worn HR sensor.
- Nomad bedside charger: Charges my iPhone and Apple Watch overnight. I use it, and many of their bands.
- Train.Red: The best muscle oxygen sensor I’ve used.
- Tymewear: Accurate heart rate and reliable ventilatory zones. I use it to pace endurance rides over an hour.
- Garmin Forerunner 970: A pro-grade triathlon watch. I use this.
- Apple Watch Ultra 4: My daily smartwatch. No phone needed on rides.
- Garmin Fenix 9 Pro: I’ve just bought one.
On the bike
- Continental GP5000 for everyday riding, and Aero 111 on the front for special occasions.
- Helmets: Specialized S-Works Evade 3 for road riding, and Rudy Project Wing for TT-style races. I use both.
- Ravemen FR300: A front light that mounts under your Garmin or Wahoo. I use one.
- Ravemen FR1000: The light and the computer mount in one unit, so nothing else goes on the bars. Better than mine.
- Ravemen FR1500SE: 1,500 lumens hanging under your Garmin, for proper night rides.
- Ravemen FR1100SE: 1,100 lumens under your Garmin, and up to 46 hours on slow flash.
- Ravemen FR500: A brighter FR300 with the same mount.
- Wahoo TRACKR Radar: I use it on one bike and Varia on the other. They perform the same.
- Garmin Varia RTL515: Radar that warns you of cars from behind. I use this model.
- Wahoo ELEMNT Roam 3: The bike computer that’s easy to use. I use mine on most rides.
- Favero Assioma Pro RS2: Accurate power pedals that swap easily between bikes. I use this model.
Home and indoor training
- NPE Runn: Makes my basic treadmill smart, sending more accurate speed and distance to my watch and Zwift. I use it.
- Google Wifi: Keeps Zwift connected in my pain cave. I use it.
- Apple TV 4K: Zwift on the big screen. I use two.
- Google Nest Doorbell (wired, 2nd gen): My video doorbell, running in both Google Home and Apple Home. I use it.
Health, recovery and sleep
- FreeStyle Libre 3 Plus: Shows how my blood sugar responds to diet.
- hDrop: Measures my sweat loss in summer and indoors.
- Fourth Frontier Zone: Checks my heart under load in hard sessions.
- Kineon MOVE+: Red and infrared light for sore knees, Achilles and other joints after hard training. I use it.
- Oura Ring 5: My partner’s recovery tracker of choice.
- Eight Sleep: A cooling mattress cover my partner and I use nightly.
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