Cold drawn or cold rolled precision seamless steel tubes Features: 1) Standard:DIN2391 GB/T3639 API5L ASTM and so on 2)Grade: 10# 20# 35# 45# and so on. 3) Sizes: O.D :10mm- 120mm; W.T:1~15mm 5) Packing:hexagonal bundle packing ,case packing,both end are potected by plastic caps or others 6)Production condition: BK,BKW,BKS,GBK,NBK 7)All steel tube can test Ultrasonic flaw detector ,eddy current flaw detector ,and Magnetic detector depend on costomers requirement