If you don't want to constantly look in the rear-view mirror to see traffic approaching from behind, the Garmin Varia 315 a compact radar detector that does just that.
It can be paired with Edge® bike computers, Garmin watches or a compatible smartphone via Bluetooth. Feedback is provided visually or acoustically on the display. The Varia 315 cannot be integrated into the Omni.
Apple Watch: If you can't or don't want to use a smartphone or driving computer, you can use the iOS app ARadar (CHF 6.-) to receive messages acoustically and haptically on an Apple Watch.
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