With this plunger (present in the fume hood in room HG01.216) small pieces of material (e.g. cells on a membrane) can be injected extremely rapidly in cold liquid propane sothat damage due to the formation of water crystals is limited. Cryo-fixation is yet an exhausive method, but the great advantage is that this approach induces in general less artifacts than chemical fixation. The next step in TEM preparation is freeze-substitution (see B).