Computer mainframe housing

Claim 1

A computer mainframe housing comprising: a metal casing having an opening at one side, first and second retainer blocks respectively projecting outwardly from two opposite lateral side walls of the casing at two opposite sides of said opening, and a rear flange projecting forwardly from a rear wall of the casing; a plastic cover having a top wall arranged to cover the opening of said metal casing, two opposite lateral side walls respectively extending from two opposite sides of the top wall of the cover at right angles, a plurality of stop rods extending from the top wall of the cover, two handles respectively projecting outwardly from the two opposite lateral side walls of the cover, two pairs of slits, one pair of slits being respectively formed in each of the two opposite lateral side walls, with the slits of each pair being formed at two opposite sides of each of said handles to enable movable sections of said opposite lateral side walls of said cover, together with said handles, to be respectively pulled outwards, and third and fourth retainer blocks respectively projecting inwardly from said movable sections of said opposite lateral side walls of said cover, wherein said third and fourth retainer blocks respectively engage said first and second retainer blocks to secure the plastic cover to the metal casing, and wherein when said movable sections and handles are pulled outwards, the third and fourth retainer blocks are also moved outwards, at which point the third and fourth retainer blocks disengage the first and second retainer blocks to enable the plastic cover to be removed from the metal casing.