Push the BT Talk Button on the handlebar to transmit and talk/listen through the intercom. Designed to communicate safely, without taking your hands off the handlebar. You transmit by simply pressing the wireless BTT Button, which is compatible with all the latest generation smartphones (iOs and Android). With BLE (Bluetooth Low Energy) technology. Ergonomically designed to not interfere with your grip on the handlebar while riding, while the silicone strap allows immediate fixing/release. Features Waterproof: Yes Bluetooth: 4.0 LE (low energy) Battery last: 2 years Here is what you find in the box: Main device, Handlebar button, Bihadesive velcro, 2 silicon band. Download Quick Guide BTT Button