Abstract: Panel apparatus includes a plurality of panels which may be fabricated or assembled into enclosures of various types, as desired by a user. Adjacent panels are secured together by any of several different types of fastening or clamp elements. The particular clamp elements are selected according to the type of structure desired to be made from the plurality of panels, or the orientation of the panels. Panels may be made of various sizes, depending on the end use, but the general size of the panel elements may be the same, and accordingly the various fastening elements are suitable for panels regardless of the overall size of the panels.