Abstract: A knock-down shelving unit comprising a plurality of rectangular sheet metal shelves supported by vertical posts having a substantially rectangular cross-section, but in two adjacent corners being provided with groove-like deformations with spaced holes to secure the shelves in selected levels by means of screws. Each shelf has box-like flange portions in the adjoining open ends of which are inserted protecting plastics plates interconnected by a flexible central portion with a guide opening for a screw to be screwed through a mounting device extending obliquely between the two flange portions near the ends thereof.