The one particular demonstrated is near the end in the USA produced knives, I believe that Camillus was producing the blades, right before production moved over seas. I do not clean 4-five deer in one sitting down so I dont require m4 (even though it is my present-day beloved) but https://alexisqgcrv.total-blog.com/the-2-minute-rule-for-fixed-blade-hunting-knife-60887649