Bluetooth 4.1 for 2 helmet and 2 device connection. With STD and HD headsets.

The SF Series was designed to offer riders the exact features they need for their ideal riding scenario. The SF1 allows 1 Bluetooth connection to a smartphone, MP3 player or GPS, while the SF2 and SF4 also offer intercom functionality for 2 and 4 channels respectively. All SF models include new features such as Audio Overlay™, Quick Charging and microphone mute functions. The SF Series boasts a sleek design with a low profile that fits almost any helmet.