Advanced two to four rider bike-to-bike communication system. Full intercom between two to four riders with bike-to-bike intercom range of up to 1.2 km/0.75 miles. Three Bluetooth intercom channels (A,B,C) for intercom toggling. Cardo Gateway for pairing with and conducting intercom conversations with non-Cardo headsets. Click-to-Link for spontaneous intercom conversations with nearby Cardo headsets with no pre-pairing required. Dual hands-free profile allows connection of two Bluetooth-enabled mobile devices or GPS. Receive in-helmet navigation instructions from compatible GPS. Mobile phone conference call with outside caller and intercom partner. Stereo Bluetooth (A2DP) enabled MP3 player works with iPod or smartphone for wireless music streaming. Rider and passenger can listen to the same stereo music via A2DP. Built-in FM radio with RDS, six station presets and smart auto scan. Parallel audio streaming allows user to conduct intercom conversations and listen to music, radio or GPS instructions at the same time. During phone conversations, music and radio are muted while the GPS instructions continue. Downloadable Cardo SmartSet app for device customization and settings can turn a smartphone into a handlebar mounted remote control. Cardo Community online platform for personalizing device settings and software updates. Customizable, self-adjusting volume according to riding speed and ambient noise. Customizable volume-per-mode for music, radio, mobile and intercom. Customizable speed dial and multilingual spoken status announcements about battery level, radio and connected devices. Multilingual built-in menus for easy operation and customization. Interchangeable hybrid and corded microphones in the same package to suit virtually any helmet type.