2-person Bluetooth Connection Built for communicating with another rider, the SF2 Bluetooth Communication System provides 2-way intercom communication up to 800 m (880 yards) in open terrain. The SF2 also lets riders enjoy smartphone connectivity allowing for music streaming, taking and making phone calls, and hearing turn-by-turn GPS directions. Plus, with the Audio Overlay™ feature, riders can simultaneously listen to music and use the intercom so you are never disconnected. Plus, with the Quick Charging capabilities, you will be ready to start your ride in no time. The SF2 is now available with high definition speakers When you purchase your SF2, you will now receive two sets of speakers! Each SF2 comes with one standard and one HD speaker set. The HD speakers will take your ride to the next level with louder, clearer quality audio. The standard speakers are a bit smaller in size and may be a more comfortable choice for some riders. The SF2 is available in a standard package with 1 headset and a dual package with 2 headsets. Stay in control with Sena Smartphone Apps You can link your SF2 Bluetooth device with the Sena SF Utility App (for iPhone and Android) to configure device settings and easily access quick guides. Also, the Sena RideConnected App will allow you to talk over intercom with a virtually limitless amount of riders over an infinite range, as long as you are connected to a mobile network. General Talk time: 13 hours Operating temperature: -10?C ~ 55?C (14°F ~ 131°F) Dimensions: Speaker Driver Unit: 32 mm – thickness 10 mm Main Module: 73.3 mm x 38.7 mm x 16.6 mm (2.9 in x 1.5 in x 0.7 in) Wired Boom Microphone: length 183 mm Wire between Speakers: length 590 mm Weight: main module - 35 g (1.23 oz) Bluetooth Bluetooth 4.1 Headset Profile (HSP) Hands-Free Profile (HFP) Advanced Audio Distribution Profile (A2DP) Audio Video Remote Control Profile (AVRCP) Audio Noise Cancellation: Advanced Noise Control™ Codec: Built-in SBC Codec FM Radio: Radio frequency specifications: 76 ~ 108MHz Intercom Working Distance: Up to 800 m (880 yds) in open terrain Supports up to 2 riders Battery Charging time: 1.5 hours Quick Charge: 30 minutes of charging equals 4 hours intercom Type: Lithium Polymer Battery