Sales, leasing, and repair of diesel and electric locomotives and rolling stock; research, development, manufacturing, sales, and repair of diesel and electric locomotives and rail transit equipment parts, automotive parts, and marine parts; sales of daily necessities, hardware, electrical appliances, chemical products (excluding hazardous chemicals), metal materials, building materials, and labor protection supplies; warehousing services (excluding hazardous chemicals); import and export of raw materials and products required for the enterprise’s production.