Standard API | ASTM | BS | DIN | DNV | GB | ISO | JIS | KS | LR | NF | Others ASTM Standard Number A 511 (Seamless Stainless Steel Mechanical Tubing) Grade MT302 MT303Se MT304 MT304L MT305 MT309S MT310S MT316 MT316L MT317 MT321 MT347 MT403 MT410 MT414 MT316Se MT431 MT440A MT405 MT429 MT430 MT443 MT446-1 MT446-2 29-4 29-4-2 [ All grade ]