APPROVED VENDOR 6ALT0 Tubing Square Corrosion Resistant Aluminum Alloy Type 6063 Outside Square 3/4 Inside Square 1/2 Wall Thickness 1/8 Length 3 ft. Mill Finish T52 Temper Outside Tolerance +/-0.010 Wall Thickness Tolerance +/-0.015 Length Tolerance +/-2.000 Tensile Strength (PSI) 27 000 Typical Yield Strength 21 000 Typical Hardness 60 Hardness Scale BHN Standards ASTMB221