a conventional plug knockout 110 of a type which is known in the art the knockout 110 is a partially cut through opening or removable wall section the knockout 110 is removed to create an opening through which a wire may pass for electrical connection to the enclosed device in the embodiment shown once the knockout has been removed it cannot be reinstalled while knockout 110 is depicted on one surface of outer wall 104 it will be appreciated that a plurality of knockouts can be positioned on any surface of the outer wall it should be noted that while the edge of knockout 110 does not appear to extend onto flanged rim 106 as will be seen in fig2 the partially cut through opening on the inside of outer wall 104 reaches the edge of the outer flange therefore the portion of rim 106 adjacent the knockout 110 is removed to form an unobstructed aperture in addition in fig1 there is depicted horizontal hinge socket 112 in pivotal engagement with horizontal cover hinge pin 114 cover locking device 116 is also shown in operative engagement with faceplate locking member 126 as explained in greater detail with respect to fig3 as is well known cover housing 100 may be formed.