More safety for cyclists - day and night Warns visually and acoustically of vehicles approaching from behind from a distance of up to 140 meters The rear light is visible from a very great distance in daylight and radiates backwards at an angle of 220 degrees so that you can be seen by drivers even before the radar perceives the vehicle. Aerodynamic design for easy mounting on most road bikes, including road bikes, touring bikes and city bikes Requires special radar display unit (sold separately) or wirelessly integrates with compatible Garmin devices Battery life: Up to 10 hours