Edge Bike Computer
The device can improve situational awareness. It is not a replacement for cyclist attentiveness and good judgement. Always maintain awareness of your surroundings, and operate the bicycle in a safe manner. Failure to do so could result in property damage, serious injury, or death.
When connected to the Varia RearVue 820 radar tail light, your compatible Edge® bike computer shows the vehicle column on the side of the screen when a vehicle is approaching you from behind.
An icon along the side of the screen represents a vehicle behind you. The size of the icon represents the size of the vehicle, as detected by the radar.
The vehicle icon moves up the screen as the vehicle approaches you, representing the vehicle's position relative to you.
The radar calculates a threat level based on vehicle size, speed, and lateral distance from
your path. An orange glow under the vehicle icon indicates that the vehicle is a mid-level
threat. A red glow under the vehicle icon with the 
symbol over the vehicle icon indicate that the vehicle is a high-level
threat.