CORRUGATED METAL ROOFING Our Simple Seal bracket with center lift utilizes 2 of our patented watertight Simple Seal bushings, and was engineered to be used on metal corrugated roofing, with fastener spacing that allows for two fasteners per metal purlin. Measures 3″ L x 1″ W x 1 23/50″ H (including 3/8″ – 16 Stud).