Stainless Steel Screw Tube Clamp. For use on Rooftop Piping, Stack Pipes, Vents Without Caps, and any Size Pipe. Band and Housing are 200/300 Series Stainless Steel. Screw is 5/16” Slotted Hex Head, Heat Treated 400 Series Stainless Steel. The High Corrosion Resistance of this all Stainless Steel Band, Housing and Screw Makes this the Perfect Clamp for Numerous Rooftop Installations.