0.3125×0.875 Oblong on 0.5625 Staggered Centers 41% - 60%, Metal Perforation Patterns, Oblong, OPEN AREA, PATTERN, SHAPE, Staggered 0.375×0.625 Oblong on 0.5625 Staggered Centers 0.3125″ x 0.875″ Oblong on 0.5625″ Staggered Centers 44% Open Area