Universal Fabrication Steel Tube Clamps for use with 1-1/2" Outside Diameter Tubing. Features: Solid cold rolled 1018 steel CNC machined parts ready to weld. -Engage thread feature helps prevent striping. -Clamp I.D. = 1.489" -Clamp O.D. = 2-1/8" -Clamp Length-2-3/4" Long -Clamp Thickness= 3/8" -Come with Stainless Steel Allen Bolts . -Set of 4 complete clamps Made In The USA.