Industrial fans are by their very nature, heavy, voluminous and largely made of steel. This means that shipping costs, either to the OEMs, such as oven manufacturers, who will fit them to their machines or to end users like the steel industry, can add enormously to the quoted cost. Additionally, shipping globally can add substantially to the price because of international tariff barriers. Fans shipped into the USA for example, attract a 27% tariff. US built fans avoid this penalty completely.