big OD seamless steel pipe 1.thickness:2.5-50mm 2.width:20-406mm 3.best quality and high prestige big OD seamless steel pipeSTANDARD: ASTM A106GRB, ASTM A53GRB API5L GRB,X42,X52,J55,N80OD:20-406MMTHICKNESS: 2.5-50MMLENGTH:5-12METERS big OD seamless steel pipe