Abstract: A fastening system for triangularly shaped surfaces is provided. Fasteners are located equidistant from the apexes of triangles formed from lines bisecting adjacent sides of the triangularly shaped surface and an apex of the triangularly shaped surface. A rotated fastener is located at the midpoint of the triangularly shaped surface. The fasteners have three bumps and possibly three dents disposed in a generally circular pattern with side walls perpendicular to the surface of the triangularly shaped surface. The rotated fastener is similar to the fasteners only rotated 60.degree.. Two triangularly shaped surfaces may be fastened together by aligning them such that the bumps from one triangularly shaped surface are received in the spaces between adjacent bumps or dents of the other triangularly shaped surface and are held closely by friction between the side walls. The fastening system is also suitable for fastening tetrahedrons or other solids having triangularly shaped surfaces.