Material: Steel posts conform to ASTM A653 Modified Grade 57 (60 ksi minimum yield), Standard Specification for Steel Sheet, Zinc Coated (Galvanized) or Zinc-Iron Alloy Coated (Galvannealed) by the Hot-Dip Process.
Shape: The cross section on the sign support post is carbon steel tube formed to square and welded directly in the corner by high frequency electric resistance welding and externally scarfed to match the corner radii.
Finish: The galvanized part conforms to ASTM A653, G90, Structural Quality, Grade 57. The corner weld is zinc coated after scarfing. The galvanized post is coated with a passive inhibitor and a minimum of 0.5 mil of clear acrylic polymer coating applied as a rust preventative.
Holes: All four sides feature holes that are 7/16″diameter, (±1/64″) on one-inch centers through the entire length of the post. Holes are on the centerline of each side, in alignment with and opposite each other directly and diagonally.
Telescoping Properties: The finished post is straight and has a smooth, uniform finish. All consecutive sizes of square tubes telescope freely and for not less than ten feet of their length without the need to match any particular face to any other face. All holes and ends are free from burrs.