... )Length:50-5600m or according to your requirement steel hollow square bar 1).Material:200,300,400series 2).Surface:cold drawing ... , Brush, Dull Finish)400G, 500G, 600G or 800G Mirror finishApplicationOrnamental tubes, Decoration construction, upholstery, industry machineTestSquash test, Extended test, Water pressure ... %≥35%≥35%Hardness (HV)<253<253<200<200 steel hollow square bar