The registration authority is zhang zhenghua, represented by legal persons and includes the production, processing and sale of filtration cores, oil filters, dust removal equipment, filtering equipment, filters, paper products, purification equipment and accessories; sales: filters, paper filters, filters, filters, filters, filtration materials (except for dangerous chemicals and easy-to-use drugs), rubber products, total filtering units, filtering devices, hardware products, hydraulic equipment, specialized equipment for environmental protection, packaging materials, pumps, stainless steel, aluminium, iron powder, iron ore, coloured metals (with the exception of approval), steel accessories, plastics (with the exception of medical treatment) and sales; production and sale of paper boxes; import and export of goods, technical agents, imports and exports (with the approval of the law, subject to the authorization of the relevant sector)*