Businesses in the petroleum products category supply fuels and other products made from crude oil or petroleum. They may operate as wholesalers, distributors, importers or specialist suppliers, serving commercial, industrial, transport, agricultural and domestic customers. Products commonly include petrol, diesel, heating oil, kerosene, aviation fuel and marine fuels, supplied in bulk or in packaged quantities according to the customer's needs. The category can also include suppliers of lubricants, greases, hydraulic and transmission oils, solvents, bitumen and related products used in vehicles, machinery, construction and manufacturing. Services may include arranging delivery by tanker or drum, storing and handling bulk products, advising on product specifications and supplying fuel-management or equipment services. Some businesses focus on particular fuel types, industries or delivery areas, while others provide a broader range of petroleum products.