wholesale Cold drawn steel pipe The s Small Diameter Tubing refers to the steel pipe with the outer diameter of the seamless steel tube with a diameter of 299MM, the diameter of the outer diameter and the thickness of the wall is less than 20, the minimum mouth is 3MM, the thickness of the wall is as low as 1MM. Small Diameter Tubing process: pipe website:http://www.skivingtubelw.com/cold-drawn-tube/