Section products are made of either blooms or billets, which are, like slabs, considered a semi finished product and are cast by a continuous caster or rolled at a blooming mill. Billets have a cross section 50 to 125 millimeters square, and blooms are 125 to 400 millimeters square. In practice, they are not precisely distinguished by these dimensions, and there is considerable overlap in the use of the two terms.