1.CE(DIN18800),ISO9001,BV, 2.Minimum Steel Quantity:Q235,Q345 3.High Construction Efficiency 4.Long life time If you need: ... Opinions 1)steel building, 2)metal building, 3) ... slope, muti slope; Sing span; double-span, Multi-span, single floor, double floors! 3) Different Bases: Cement and steel foundation bolts4) Different Columns ...