Schuberth SC1 Advanced fits in all C4, C4 Pro and R2 helmets. Powered by: Sena Chipset: 10R/10U Talk time: Up to 14 hours Charging time: 3 hours Intercom working distance:> 1000 m (Distance for carbon helmets approx. 350m) Intercom participants: 4 Bluetooth sources: 2 Automatic gain control: Yes FM Radio: Yes Standby: 1 week Smartphone App: iOS, Android Included remote control: No Optional remote control: Yes VOX voice commands: Yes Music Sharing: Yes Audio-Multitasking: Yes (With software version 2.0) Installation time: 1 minute