... Copper,Plywood,Fiberboard,Rubberboard,Woodboard,Pasteboard,Al-Mg.alloyplate,,Nickel-plate,Fiber.glass,PVC.plate ,Composites.SpecificationWe can ... the more material distortion takes place, especially when the perforated pattern is bordered by margins on all four sides. ... on thickness, pitch, openings, flatness, and shearing for perforated products. You should specify a specific tolerance ,so we ...