Detailed Product Description 1:Size: 16-168mm(OD) ; 1.5-30mm (WT)2.Standard: ASTM, API, JIS, DIN, GB3.Surface:oiled or black painted to prevent rust4.Marking:as the customer required. Material: cold-drawn steel pipeApplication: Carbon seamless steel pipe used in kinds of fields, they can transmit oil, water, and gas.