Some upscale models will have color LED displays, which will be able to show the CD cover of a song being played and other types of graphic information. About the size of a radar detector, this unit fits into a docking sleeve that connects to any auto or home audio system. While digital radio will come from the sky first, within two years, many conventional land-based stations are also expected to begin broadcasting digital signals. But the stations will also broadcast in AM or FM, allowing listeners to upgrade to digital at their own pace. They're now available on uplevel minivans from Ford, DaimlerChrysler, GM, Honda, and Toyota, as well as from a number of aftermarket manufacturers.
Many systems now incorporate wireless headphones.
Some companies are taking wireless technology even further. Amtel International, for instance, recently introduced a portable system that uses wireless components. The monitor's rechargeable battery is claimed to last from two to three hours. DVD systems are now offered by Acura, Honda, and Lexus. Portable navigation units provide some of the key functions of an in-dash system but are transferable between vehicles.