1) Sizes (O.D. x T): from 6 x 1mm to 168 x 12mm 2) Standards: ASTM A192 (ASME SA192), ASTM A106, ASTM A213, JIS G3461, JIS G3462, DIN 17175, BS 3059 3) Surface: oiled or black painted to prevent rust 4) Marking: as per customer's requirement Commonly used steel grade: 20G, 20MnG, 25MnG, 15MoG, 20MoG, 12Cr1MoVG, 15CrMoG, 12Cr2MoG, 12Cr2MoGVWTiB, 12Cr2MoVSiTiB Inner packing: Caps on two ends of every pipe Outer packing: Hexagonal shape bundles wrapped with strong steel trip or according to customers' requests