Abstract: A storage cabinet, comprises a generally rectangular open front housing having a rear wall joined to a top wall, bottom wall, and side walls, a plurality of mounting grooves, each groove extending horizontally along the inside back wall and side walls of the housing, a plurality of storage units having mounting edges adapted to be selectively mounted in the housing in selected ones of the mounting grooves, wherein at least one of the storage units having a width less than the full width of the interior of the housing, at least one latching device for latching each of the storage units in one of the mounting grooves, wherein at least one of the storage units is supported solely by the storage unit mounting edges engaging one of the mounting grooves along a portion of the back wall and one of the side walls.