Abstract: A door unit for an enclosure (1), as for example a shower recess or a combined shower/bath, is provided which includes a first panel (20, 301) which is pivotably movable relative to a wall (3) of the enclosure and at least a second panel 21, 302) which is movably and rotatably connected to the first panel (20, 301) at least one of said panels having a roller track associated with an upper end or extremity thereof and the other panel having one or more roller brackets associated with an upper end or extremity thereof, to allow the panels (20, 21 and 301, 302) to be relatively extensibly one to the other, the unit also including means (100) for releasably retaining said panels (20, 21 and 301, 302) in an extended relationship to one another.