Sk125/5.5" 4.5mm 85bar twin wall pipe Location: concrete pump two wall pipe Type:two wall pipe Material:inside layer nm600 seamless pipe induction hardened Outside layer st52 seamless pipe Inside layer:55mn seam pipe induction hardened Outside layer: q235 seam pipe Inside layer:65mn seam pipe Outside layer:q235 seam pipe Wall thickness: 4.5mm(2mm+2.5mm)