Gaskuropack 54 consists of porous polymer beads made of a poly (styrene-divinylbenzene) copolymer with a high degree of bridging. This packing has been specially treated to confer high thermal stability, and has little batch variation. As it is a porous polymer, it is suitable for work environment determinations which are almost free from ghost peaks due to water or air. If coated with a liquid phase, it can in some cases permit analyses which were difficult to carry out with diatomaceous earths.