The Sena pi is a universal Bluetooth Intercom system that turns your favorite outdoor-sport helmet into a Sena smart helmet with 2-way Bluetooth Intercom, no data plan or cell service required. It also serves as an audio output device, as it can pair to a smartphone so the user can listen to music, make or take phone calls, and listen to GPS navigation. The pi's compact 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 (0.7 in). The unit's two-button control scheme, located on the left speaker, makes it easy to control on-the-go. Sena's pi is ready to go out of the box: just clip it to your helmet, press the two button on the unit to turn on the unit, and you're ready to connect with another user.