Ключевые слова: angle, background, bolt, brass, bronze, chrome, close, closeup, connection, device, equipment, fastener, fittings, inclined plane, industrial, industry, instrument, iron, machine, mechanism, metal, nonreturn valve, nut, nut and bolt, object, old, plug, plumbing, power, projector, restraint, screw, silver, steel, technology, tool, tools, valve, wealth, wrench, yellow,