Ключевые слова: background, board, catching, circle, cog, compare, concept, connection, dark, design, dirty, engineering, equipment, factory, gear, gearing, gearwheel, grey, grunge, hang, icon, industrial, industry, machine, many, mechanical, mechanism, metal, motion, motorbike, much, nobody, part, plain, red, round, sample, shape, size, spare, sprocket, steal, symbol, system, teamwork, technical, teeth, toothed, white, work,