Current MOD4 knives are made by J Adams. Rockwell is 54 of a plain carbon steel with a small percentile of nickel. The older WS are lovely and closely match the Martindale paratrooper machete. 'Out of the box' J Adams come with a left handed leather sheath insulting to the sacrifice of the animal. Throw it away. The black fiber handles are impossible to sand. Buy the civilian wood version and sanding improves the very uncomfortable grip. The guard is spotwelded and a rare accident can break it free. The 1/4" thick blade has virtually no edge and a horrid angle. It is readilly reprofiled due to the soft temper. Sadly, it loses the edge almost as fast. I locked myself in an abandoned caravan and picked a fight with my MOD4. It took the better part of an hour hacking,prying and smashing through marine plywood, duraluminum skin, electrical conduit and fiberglass insulation. The edge was a hopeless mess. In fairness though a fine mill file brought it back to usefullness in short order. For all the shortcomings, I would love an older WS. For all the empirical shortcomings, it still works somehow.