Transfer system

A transfer system for use in transferring cryogen from a source to a point of use, comprising a flexible conduit for through flow of cryogenic fluid, heating means external of the flexible conduit arranged to provide heat to a wall of the conduit, and control means associated with said heating means for maintaining the temperature of said wall of the conduit at a level whereby cryogenic fluid flowing through the conduit is maintained in Leidenfrost flow and wherein an operating head comprising a chamber for cryogenic fluid communicates with said conduit, the chamber having an external wall across which heat exchange can take place and filamentary material within the chamber in contact with the external wall of the chamber which provides an increased internal surface area in the chamber on which the cryogenic fluid evaporates to effect heat exchange.