The Garmin Varia eRTL615 rearview radar for e-Bikes is Garmin's first battery-free radar. It plugs directly into your compatible e-Bike and detects cars approaching from behind and provides audible and visible alerts when paired with your compatible Garmin smartwatch, bike computer or even your smartphone with the Varia app. Battery-free 24 GHz rearview radar and tail light for compatible eBikes (requires compatible Garmin eBike cable; sold separately), Radar detects vehicles approaching from behind up to 150 yards (140 meters) and integrates with select Garmin wearables, Edge bike computers or the Varia app on your compatible smartphone to provide alerts, Tail light provides daytime visibility up to 1 mile away and has 4 light modes: solid, peloton mode, night flash or day flash, Sleek and compact design offers multiple mounting options with universal seat rail mount or rack/pannier mount, Offers ANT+ technology and BLUETOOTH Low Energy connectivity for pairing with compatible devices and apps, Update software by using the Varia app on your smartphone or Garmin Express software on your laptop. WHAT'S INCLUDED: eRTL615 (direct rack mount), 2-bolt to friction flange mount adapter, seat rail mounting kit, documentation. DETAILS: 3.9"H x 0.8"W x 1.6"D, Weight: 0.15 lbs., Wireless: ANT+, BLE, Wireless range: 20 ft., Compatability: iPhone & Android, Manufacturer's 1-year limited warranty. For warranty information please click here - https://cs.kohls.com/app/answers/detail/a_id/140, Model no. 010-02788-00,. WARNING: This product may contain a chemical known to the state of California to cause cancer, birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov - https://www.p65warnings.ca.gov/. Size: One Size. Color: Black. Gender: unisex. Age Group: adult. Material: NONE.