12C27 is a classic Swedish Sandvik steel used for many outdoor knives and very popular with French manufacturers like Robert David. Sometimes, 12C27 is used for mass-produced razor blades. Depending on the heat treatment, its hardness can be above or below 440C.

Origin: Sweden
Carbon (%): 0,58
Chrome (%): 14
Manganese (%): 0,35
Silicon (%): 0,35
Rockwell (HRC): 58-60