Abstract: A hot or cold body pack utilizing a heat transferring element which includes a bag having a first heat insulative portion and a second heat porous portion. The heat porous portion also mechanically retains a heat transfer element within the bag. The bag includes an opening to retain the heat transfer element. First and second loop members extend along separate dimensions on the outer surface of the bag to permit the straps to hold the bag to a body. Fastener material along an edge of the bag allows it be fastened to another pack.