There are now a number of ebikes equipped with radar systems which warn riders of vehicles approaching from behind. If your bike isn't among those, you can now change that by slapping on Garmin's Varia eRTL615 radar/tail light module.
Garmin Varia eRTL615 eBike Rearview Battery-Free Radar with Wearable4U E-Bank Bundle : Electronics
Garmin Updates Varia System With E-Bike Connectivity
IN THE BOX: 1x Garmin Varia eRTL615 (direct rack mount), 1x 2-bolt to friction flange mount adapter, 1x seat rail mounting kit, 1x Wearable4U E-Bank,
Garmin Varia eRTL615 eBike Rearview Battery-Free Radar with Wearable4U E-Bank Bundle
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Garmin Updates Varia System With E-Bike Connectivity
New Garmin eRTL615 ebike radar
New Garmin eRTL615 ebike radar