Alloy tool steel for cold work, thanks to chemical elements(Cr, W, Mo, V)  included in the composition has a high 
hardenability and increases its resistance to twisting, bending and abrasion. In particular, the grades containing about 2% C, 12% Cr, 
characterized by a very high resistance to abrasion. Steels with carbon content 0.40 - 0.55% is used for the production of tools 
operating at dynamic loads, steel with carbon content of 0,75-2,10% is used for making some cutting tools, to the production
rolls, etc.
In the grade marking the letter N stands for steel for cold work, in the second place (as in the case of steel for hot work) is 
a letter or a group of letters identifying the alloy component or group of components:

M - Manganese 
S - Silicon
C - Chrome
N - Nickel
L - Molybdenum
V - Vanadium
W - Tungsten
K - Cobalt
P - Nickel + Chrome + Wolfram 
Z - Vanadium, Tungsten + + + Chromium Silicon 
B - Boron

In the third place there is the number (in the middle or the end of the grade marking), which classifies the steel in terms of the 
difference in the amount of alloy and carbon, or as in the case of steel with the same alloying additions, distinguish these grades, 
eg NC6-NC10, CC2-CC3. 
For example, NPW steel sign - means the tool steel for cold work containing chromium, nickel, vanadium and tungsten.

NC6 - chrome-vanadium steel
NPW - steel nickel-chromium-tungsten-vanadium
NCMS - chrome-silicon-manganese
NWC - tungsten-chromium-manganese
NZ3 - steel tungsten-chromium-silicon-vanadium 
NMV - manganese-vanadium steel
NC11LV - chrome-molybdenum-vanadium