Forever raising the bar for themselves, the manufacturer has taken their well-respected D-2 steel powderized and re-smelted to achieve CPM D-2, which has more evenly distributed carbides, adding even better wear resistance to an already impressive steel.
Considered a high carbon steel in this more distributed state, regular D-2 does air-harden which could present difficulties for the amateur maker. However, when heat treated and ground properly, CPM D-2 is a monster in any application, taking everything the user throws at it and then asking for more.
The high carbon and carbide density translate to an edge that forms a burr that is commonly described as eerily sharp no matter the abuse and use.
If there is any downside to this steel is that it may not offer the best corrosion resistance, but when well maintained and cared for, makes a knife worth several lifetimes. Popular for folding, tactical and Japanese style Katsu knives.