... 304H,309S,310S,316,316L,321, About 300 series stainless steel welding wire300 series stainless steel welding wire are with high chemical inertness ... electron, chemical, aviation. stainless steel welding wire products:A) Material Classification: 200 series: 201, 202 … 300 series: 301,302,304,304L, ... 304H,309S,310S,316,316L,321,347… 400 series: 410,420,430,431,434…B) Hardness Classification:Soft ...