Sorry, Bernie, but I don't know, but if I had to guess, I would say that they are using either a form of 400 series steel, now which version, beats the heck out of me. Their home page says nothing. You should maybe call them and could tell you. Chances are they are using a Japanese made steel of good quality(I would Hope anyway). Good Luck. If you find out post it, I'm always interested in knowing about what steel some companies use.