Your iPhone already has a speakerphone mode, letting you drive and talk (or wait, on hold) without lifting a finger. Realistically, however, we try to avoid using the phone’s speaker mode because call recipients are treated to the classic “I’m calling you from a speakerphone” audio quality—not to mention the fact that it’s not totally legal in many places, since the iPhone’s touchscreen doesn’t work for no-look dialing. Kensington’s add-on Hands-Free Visor Car Kit for iPhone includes several great one-touch dialing features, and its audio quality roughly matches that of the iPhone handset.

Several large front buttons make the Kensington device look like a sleek garage opener; it’s even designed to hang from your sun visor. At about the same footprint and twice the girth of an iPhone, we could easily leave it clipped to our visor after parking or carry it inside.

In our fantasies, Kensington's Car Kit makes speakerphone calls and opens your garage door too.

Up to three Bluetooth phones can work with the Car Kit, making it an uncommon, multiuser Bluetooth device. It takes a minute to first pair the phones—say yours and a spouse’s—then the device automatically connects when a paired phone is in range. If it doesn’t make the connection, a button toggles between registered phones in sequence.

The device remembers three speed-dial preferences for each handset too. After you place a call, you’ll hold one of those buttons a moment to record the number within the Car Kit. You don’t even need to touch your iPhone to call that person back; just hit one of those big buttons. We easily made calls without fumbling with our iPhone’s touchscreen—although you can still dial out that way, if you prefer.

The Car Kit’s battery power will outlast your iPhone’s. We talked for hours without bottoming out. Kensington says the Car Kit will run for ten hours of talk-time in one go. But that rating hardly matters, since the kit includes an extra battery and USB and 9-volt chargers. The device can’t draw power directly from your car’s 9-volt charger, but you should always have a fresh battery to swap in.

We placed many calls to unsuspecting mobile and landline contacts, only later revealing our Folger’s Choice–style quality survey. Most people thought the speakerphone connection sounded about as good as—or better than—our typical iPhone calls. However, a few friends couldn’t understand us well until we switched back to the iPhone mid-call. (We called them back with the same results.) Without exception, we heard everyone clearly from the speakerphone. After listening to our call recordings, we thought the Car Kit microphone sounded perfectly intelligible, although the iPhone handset created slightly deeper and fuller sound in a direct comparison.