... transportation. Size: 1/2"-40" 1)Product name:&CertificateSeamless Black Steel Pipe & ISO900, API2)Standard executived:ASTM:ASTM A335 ... 4541 ,ST33,ST37,ST37.2,ST35.8,ST35.4,ST42,ST42.2,ST45.8,ST45.4,ST52.4,ST52,TT ... Type of end:plain end, beveled end8)Surface Treatment:black painted to prevent rustblack,3PE coating and so on, ... ,DIN2448 Seamless,welded ST37.2/ST52.4/ST35.8 carbon black Steel Pipe