square steel tube material :Q195 Q235 GR .B with own factory thickness:0.3-2.5mm StandurdGB/T6725,GB/T3094,TSAM A500,EN10210,GB/T9711.1-1997, API Material:Q195, Q215,Q235,Q345,ST37-2,ST52-3,S235,S355, 20#etc Diamete20*20---800*800Wall thickness0.6mm-45mm Length 4.5mm-12mm or as per the client's requirementPacking1. in bulk 2. packed by steel strip into bundle 3. according to client Finish black, ...