Abstract: An antivibration guide is disclosed for use in removably mounting printed circuit cards in metal racks. The guide is composed of plastic, having a U-shaped cross section for receiving and holding the P.C. card; and the guide includes at least a pair of vibration dampening buffers. Each buffer includes a pair of vibration dampeners, located on opposite sides of the P.C. card, with each dampener including: a pair of flexible legs connected to the side walls of the guide, and further including a midportion having a pair of vibration dampening surfaces which engage the side edges of the P.C. card and reduce the vibration of the P.C. card.