I'm a machinist and I bought this Chinese made die for a one off order to save a few bucks. This die does not screw on properly and the customer service has been less than satisfactory. I bought a crystal from TMX for $3-4 more and it worked great. The problem with this matrix is that it doesn't work properly and on further searching the mechanics forums many others have encountered the same problem and ruined some projects. HSS is low quality and please take my advice seriously as you will regret buying this product.