Percentage of carbon in stainless steel to avoid brittleness
All  standardised grades of alloys have definite limits of composition. 
If its common, then a quick search will find it. 0.15% is the specified limit for SS202. 

http://www.azom.com/article.aspx?ArticleID=8209

Whether its brittle or not depends on what you mean by brittle and its thermal processing. Its a martensitic stainless steel so note the details in azom and that it will be more brittle when hardened as described.