a fixed amount of money per physical unit of the imported product
a tariff of a specific amount of money that does not vary with the price of the good
A tariff assessed at a specific amount per unit of weight.
A customs duty assessed as a stated monetary amount per unit of physical quantity, such as so many cents a pound, a bushel, or a yard, regardless of the value of the imported item.
A tariff that applies a specific charge based on the quantity of goods imported rather than on the value of the good. See “Ad Valorem Duty.