CPM-M4 is a powder-metallurgical high-performance tool steel that offers excellent edge retention and stability. Due to its chromium content of just 4%, it is quite susceptible to corrosion and might show rust just from being carried in a pocket.

Origin: USA
Carbon (%): 1,4
Chrome (%): 4
Molybdenum (%): 5,25
Manganese (%): 0,3
Silicon (%): 0,55
Copper (%): 0,06
Wolfram (%): 5,5
Rockwell (HRC): 60-62