Plumbing installation and construction. General items: metal material manufacturing; metal material sales; electronic product sales; metal daily necessities manufacturing; hardware product manufacturing; hardware product retail; hardware product wholesale; household appliance spare parts sales; household appliance manufacturing; household appliance sales; lighting fixture manufacturing; lighting fixture sales; R&D, production, and sales: rubber and plastic materials, glass fiber and products, rubber products, plastic products; sales: building materials, chemical products (excluding hazardous chemicals), insulation materials, anti-corrosion materials, furniture, and home appliances.