Bluetooth Intercom - Bluetooth 4.1 Pi Universal Bluetooth Intercom A compact headset, pi's design makes it easy to attach to most cycling or skating helmets, or any other helmet with a strap width of up to 18 mm Device operation utilizes a two-button layout located on the left speaker Just clip the Sena pi to your helmet straps, hold the buttons to turn on the device Pi features 2-Way HD Intercom allowing you to pair your headset to a friend's to instantly communicate; no cell phone or data service needed Whatever outdoor activity you enjoy with a friend, wind noise can be disruptive to your conversation. Thanks to Advanced Noise Control, that’s not a problem with the pi universal multi-sport Bluetooth intercom. This feature diminishes ambient noise such as strong winds, ensuring your audio is transmitted clearly Pair your smartphone to pi via Bluetooth connectivity. Listen to your music, hear GPS navigation, and even take phone calls, all hands-free The Sena Utility App gives you total control of the pi through your smartphone. Adjust setting without missing a beat, such as enabling voice prompts or selecting whether to prioritize music or voice on audio General Dimension: 30 mm x 59 mm x 13 mm (1-3/16" x 2-5/16" x 1/2") each unit Mountable helmet strap width: up to 18 mm (11/16") Weight: 37 g (1.3 oz) Charging temperature: 0°C~45°C (32°F - 113°F) Operating temperature: -10°C - 55°C (14°F - 131°F) Battery Talk time: up to 6 hours Charging time: 2.5 hours Type: Lithium Polymer Battery