"It consists of two plastic brackets, which are affixed to the side of a hard drive. There are rubber buffers that then bridge the gap between the hard drive and the case mount. The idea is that the hard drive is not held in place by any metal, thus stopping vibration. This in turn reduces the amount of vibration passed onto the case chassis."
FULL STORY @ PC-ARENA (http://www.pc-arena.net/Review_full.asp?ReviewID=181)