The valves are a set of parts that  allow the entry of  air-fuel mixture to the combustion chamber (admission)  and the leakage of  resulting gases (escape).

In order to achieve this objective, NPC ® presents its valves with TUFFTRIDE ® coating,  an epsilon ferric nitrate and hard coal compound, that generates a thin surface layer mainly in the valve stem, improving the friction between this and the valve guide.   This coating  has a diffusing layer that improves in a double proportion its capacity of  preventing the fatigue and producing corrosion  resistance of the treated materials.

The NPC ® valves benefit from the properties of TUFFTRIDE ® that makes them more wear resistant,  extending its life span.