Agent 18, purveyor of fine cases for the iPod, has thrown their hat into the iPhone ring with a number of models for Apple's handset. Among them is the DiamondVest, a silicone skin billed as featuring a "rugged design."

The DiamondVest comes only in black; it's easy to slip onto the phone, as it's just one piece of silicone with a large opening for the iPhone's touch screen. You'll also find holes in the case for the Ring/Silent switch, Wake/Sleep button, headphone jack, dock-connector port, microphone, and speaker. On the back is a small opening for the iPhone's camera lens, and on the left side are two raised bumps that let you easily find and use the phone's volume controls. Another raised nub on the front of the case sits right over the Home button.

One nice touch of the DiamondVest is that it's covered with a pattern of diamond-shaped bumps that mimics "diamond plate" metal. As with the metal, the design makes it easier to grip the case, reducing the chances that the whole shebang will slip out of your hand. The silicone is pleasantly thick—enough that I wouldn't worry about everyday bumps and scratches—but it doesn't add much bulk; the encased iPhone is still thin enough to slip in your pocket.

The major shortcoming of the DiamondVest, however, is that it doesn't protect the iPhone's touchscreen, which is potentially the most sensitive part of the phone. This makes it easy to use the MultiTouch interface, but if you're concerned with protecting the screen from scratches or other damage, the DiamondVest may not be precisely what you're looking for; several similar cases from other vendors include a clear, protective film for the screen. If the lack of such protection doesn't bother you, the DiamondVest is a solid offering in the silicone-skin market. --Dan Moren

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