The Sena Technologies 10U Bluetooth Communication system was built and designed with the helmet in mind. The 10U is discreetly hidden inside your Arai full face helmet without all that extra weight hanging off to the side. Connect up to 4 riders over a 1 mile distance all while being able to listen to your music or take a phone call.; Includes Handlebar Remote for easy use Connect up to 4 riders 10hr Talk time Advanced Noise Control FM Radio Bluetooth 4.1 Voice prompts Discreet design 1 Mile range Works with Arai full face helmets