Ключевые слова: abstract, assembly, background, bolt, bolthead, building, connection, construction, contemporary, fastener, fastening, gray, grey, hardware, head, hexagonal, hexahedral, hexahedron, industrial, industry, inscription, iron, joint, many, material, metal, metallic, mounting, new, number, nut, panel, screw, silver, silvery, site, standard, steel, strengthening, structure, surface, texture, thread, threaded, wall,