These can be manufactured with different kinds of perforations, of which the main ones are round, square, rectangular, oblong, tapered and bridged. Standard size is 2000×1000 mm, however the machines used enable perforation of plates up to 6000×2000 mm. Thickness of the plates varies from 0,3 mm to 20 mm for plates in carbon steel and up to 15 mm for stainless steel plates. It is possible to obtain plates with perforated areas in special geometric shapes, for example trapezoidal or circular crowns. After perforating, the plates are straightened and may undergo degreasing treatment to eliminate residues of the lubricant used during the punching process. Plates with different levels of surface finishing can also be supplied, attainable through butter-finishing, sandblasting and electrolytic polishing. They can be produced in different materials, such as for example, carbon steel, stainless steels, Nickel-Chromium alloys, pure metals.