This feature allows you to pair your phone to the Prius' audio system and have hands-free calling utilizing the speakers in the car and a microphone next to the front dome lights. You can also dial numbers and store contacts on the Multi-Function Display (MFD). Bluetooth is identified by a fourth cluster of buttons on the upper right section of the steering wheel. These buttons are used to answer and end Bluetooth calls. Bluetooth was an available option on all 2004-2009 models. There are also many aftermarket options available for cars not equipped with this feature.