Generally, there are only two types of hardware: 1. Big hardware refers to steel plate, steel bar, flat iron, universal angle steel, channel steel, I-beam and all kinds of steel; 2. Hardware refers to building hardware, iron sheets, locking nails, iron wire, wire mesh, wire scissors, household hardware, various tools and so on.
As far as the nature and use of hardware are concerned, it should be divided into eight categories: iron and steel materials, non-ferrous metal materials, mechanical parts, transmission equipment, auxiliary tools, working tools, building hardware and household hardware. Specific products include large-scale mechanical products and small-scale tool products.