IceJax I Snow Guards 20pcs Screws and Sealant Kit for Metal and Steel Roof Panels Includes 40 galvanized #14, self-drilling screws, 2 inches long, with an attached neoprene washer. Fits most metal panels and all standing seam panels, reversible for rib straddling! Starter points are provided for mechanically fastening. ATI lab tests show 4200lbs strength with mechanical attachment. Free layout at www.SpacingTool.com