Abstract: A pipe fitting adapted to be installed in an aperture in a wall of a fluid container, comprises inner and outer co-axial sleeve members interconnected for relative axial movement and a split, helically wound, washer. The inner sleeve member has an end portion insertable through the aperture, and the outer sleeve member has an annular bearing surface adjacent to the end portion adapted to overlie a first one of two opposed surfaces of the wall around the periphery of the aperture. The split washer is retained to and extends around the end portion opposite the bearing surface, and is of larger outer diameter than the aperture but is insertable therethrough by winding so as to overlie the second of the opposed surfaces of the wall.