OtterBox has announced the release of the Defender series case for the iPhone 3G. The new case will retail for $49.95.

The OtterBox Defender features three layers of protection: a polycarbonate membrane that prevents scratches or dirt, a sturdy polycarb shell, and a smooth silicone skin that helps to absorb impact and also gives the case a tactile feel for easy handling.

The Defender for iPhone 3G allows access to the iPhone’s silence switch, and also provides an improved screen and better fit and feel, based on the company’s statements. The key buttons of the phone all remain accessible, including the volume and sleep/wake buttons. Acoustical vents have been incorporated to allow clear sound to pass between the microphone and speakers, so it won’t block your iPhone’s audio output.

The case includes a holster swivel belt clip which converts into a display stand when the iPhone is placed facing screen-out on a surface.

The OtterBox Defender is available now in black, and will be released shortly in white, black and yellow, and pink.