name :seamless steel tube Standard: ASTM,GB,API Thickness: 3 - 60mm 1Goods: Carbon Steel ... ,2.2-1/2,3,4,5,6,7,8,9,10,11,12,14,16 4Thickness(mm):0.2-40mm ... 5L, ISO,CE, BV, 12Standard: ASTM A53/A106, API 5L, Gr.B/DIN, BS1387, DIN2440,GB/T8163, GB/T8162,GB/T3087 ... countries and regions, well received by our buyrer. seamless steel tube