Introducing completely integrated Sena 10U Bluetooth communications technology from Sena, designed specifically for the Klim Krios Adventure Helmet. Available pre-installed or as separate upgrade. Bluetooth 4.0 technology Unibody design is built specifically for the Klim Krios Adventure Helmet and fits into the helmet ear pockets Includes a wireless remote control as well as a three-button control pad Four-way intercom communication up to 1 mile in open terrain Universal Intercom to communicate with other brand headsets Group Intercom Voice prompts Music sharing between rider and passenger Firmware upgradeable Smartphone app for iPhone and Android Talk time: 10 hours Dimensions: Microphone with control unit: 77 mm x 68 mm x 58 mm (3.0 in x 2.7 in x 2.3 in) Profile: Headset Profile, Hands-Free Profile (HFP), Advanced Audio Distribution Profile (A2DP), Audio Video Remote Control Profile (AVRCP) Built-in SBC Codec Advanced Noise Control Wide volume control Sample rate: 48kHz (DAC) Built-in wide band Codec (HFP) Sample rate: max 16 kHz Built-in FM radio with RDS AF (Radio Data System Alternate Frequencies) Radio region: worldwide Radio frequency specifications: 64 ~ 108MHz 10 preset station memory with automatic scan function Radio on time: 8 ~ 10 hours Charging time: 3 hours Type: Lithium polymer battery Certificates: CE, FCC, IC