The SatStation Privacy Handset is an optional feature to add to your choice of SatStation Dock Plus. The Privacy handset is able to transmit and receive audio via a sleek and lightweight design. You are able to take calls in your car and keep them personal. The way it works is simple-the handset is plugged into the dock station via a manufacturer-installed RJ11 port. This handset was designed with your needs in mind. When you lift the handset, the hands-free speaker and microphone are muted on the car kit, and you can carry on a private conversation with out the disturbance of background noise. The SatStation is also built with a light indicator for night use. This small addition to your SatStation Dock is a great way to optimize all the features and convenience of your Iridium Dock.