OtterBox's latest cases, the Defender and Impact Series, promise to protect from both iPhone 3G and 3GS models from dust, drops, and dirt without compromising functionality.

So, the scratchproof Defender Series ($49.95) allows for interaction with iPhone's volume control, camera, touch-screen, silent switch and phone functions in spite of three layers of protection. One layer safeguards the screen from scratches, dust and dirt. A polycarbonate shell fortifies the device against drops or impact. And a silicone skin absorbs shock and keeps dust and dirt out of all ports and plugs. 

At the $19.95, the cheaper Impact model is less pricey, but with a high level of protection as well. It has an inner coring that dissipates impact away from your iPhone to protect from bump and shock. An included, self-adhering screen cover adds additional protection from scratches. As with the Defender, this case offers complete interaction with device functions.

The OtterBox Defender Series comes in black, yellow/black, white or pink and the Impact Series is available in black or white.