Midland BT1 Bluetooth Intercom System for ATV (Pair) Wireless Intercom System Rider & Passenger System Compatible With Most Helmet Types Compatible With Other Bluetooth-Enabled Devices Such As Cellular Phones, Gps Systems, Mp3 Players & Two-Way Radios Passenger Unit Pairs With Main Device Complete weather-resistant Bluetooth intercom system for a motorcycle rider and passenger Bluetooth connection to cell phone/GPS unit for rider unit; 3.5mm input for both Automatic gain function controls the volume in relation to background noise Two pairs of wind-resistant, noise-canceling microphones included to fit open-face/flip-top helmets Two-year manufacturer's warranty