Pre-plumbed shower door system

A shower door system in knocked down form including a door and optionally one or more return panels for forming a shower enclosure, including a pre-installed shower mixer valve mounted in a frame member of the shower door system, a pre-installed shower rose or shower rose connection fitting mounted in a frame member of the shower door system, and pre-installed plumbing from the mixer valve, within a frame member or members, to the shower rose or shower rose connection fitting, so that when the shower door system is subsequently assembled and installed against a wall or in a corner between two walls to form a shower enclosure with a frame member adjacent a wall, water supply plumbing to the shower may pass from the wall directly to the frame member to connect to the shower mixer valve, said frame member which will be adjacent a wall when the shower door system is assembled and installed including an external face, an internal face towards the interior of the enclosure, one side face which will lie adjacent a wall when the shower door system is installed, and a face or edge opposite said one side face and which is adapted to retain an edge of a glass or non-glass panel of the shower door system or which provides a vertical seal for a door of the shower.