Aluminum Round Tube, Aluminum, 6063, T52, Round, 36 in Overall Length, Outside Diameter 4 in, Inside Diameter 3.75 in, 0.125 in Wall Thickness, Fabrication Extruded, Heat Treatable Heat Treatable, Mechanical Finish Mill, Yield Strength 21,000 psi, Tensile Strength 27,000 psi, 60 BHN Brinell Hardness, 17 HRB Rockwell Hardness, Includes Material Certificate Material Certificate with Lot Number, Standards ASTM B221, System of Measurement Inch