Sometimes less really is more.

Take the solar-powered LG HFB-500 Bluetooth hands-free cell-phone kit, for example.

When you're cruising down the highway, you don't want to have to — and in many states, legally can't — use one hand to hold a cell phone up to your ear.

Many companies have been marketing kits that let you talk on the phone without using your hands, but this is the first that needs no external power.

Let's start off with appearance. The device is a little thinner than a deck of cards, and roughly the same length and width.

On one side, there's a solar cell. The other side has an on/off switch, a speaker and a large section that's really just a big button to answer calls without having to take your eyes off the road.

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The sleekly designed HFB-500 fits into a clear plastic holster that secures to the inside of your car's windshield with two small but very effective suction cups.

Volume-control buttons are not quite as easy to get to while you're driving, positioned as they are on the side edges of the device. Presumably, once you set them the first time, you won't need to adjust them very often.

The LG HFB-500 also comes with a cigarette-lighter charging adaptor, though in about a month's worth of use I've never needed it. LG claims that for every two hours of sunlight used to charge the device, you can get an hour's talk time.

So unless you're talking on the phone in your car for more than four hours a day, you should never need more than the sun to keep the HFB-500 charged.

If, like me, you already have too many wires dangling in your car for your GPS navigator, iPod charger and other devices, this certainly offers you the advantage of functionality without further clutter.

I attached the device at the top of the windshield, well out of my general line of vision. That also meant the windshield's top-edge dark tinting partly hid the unit from outside view.

Obviously, safe is better than sorry, and many users might want to simply remove it when they get out of the car.

Call me lazy and lucky to be living in the boonies, but I generally just leave it in the car unless I'm going someplace where cars are a target, such as the parking lot at the local mall.

To turn on the device, you simply hit the red button. A series of rising tones tells you it's powering up. Another double tone tells you the device has mated with your cell phone. The reverse happens when you power off.

Sound quality is only fair, but I've had no problem either understanding callers or being understood.

The functionality is simple and effective. It answers calls. Hit the big button, which takes up more than a quarter of the unit's face, to answer a call.
The same button will enable you to call back the last number whether it was a call made or received.

Unlike some other hands-free devices, this one doesn't play through your stereo system, doesn't have a built-in phone book and doesn't speak to you with a French accent. But it sure does what it's supposed to do, simply and consistently.

And oh, yes, if you're into the whole green thing, there are no batteries needed — just sunlight.

LG's suggested retail price for the HFB-500 is $99, though I've seen it advertised online for as little as $82.