R&D, design, production, processing, sales, repair and maintenance: shot blasting machines, sandblasting rooms, wear-resistant parts, steel shot abrasives, environmentally friendly dust removal equipment, general hardware, welding and cutting equipment and accessories, machine tools, automated production lines, non-standard mechanical equipment and accessories, domestic commerce, material supply and marketing industry; import and export of goods or technology (except for the import and export of goods and technology prohibited by the state or involving administrative approval).