twinwoods-spanner

Nitrotec® (nitriding-oxidising-protection) is a patented thermo-chemical diffusion process, during which the surface of steels, is nitrocarburized and next oxidized and cooled.  Nitrotec® combines the useful properties of the nitrocarburizing (improved surface hardness and wear resistance, enhanced fatigue strength, no material distortion) with the high resistance against atmospheric corrosion, increased yield strength and an almost-black finish.

In short this process adds hardening, strength and corrosion resistance.  Additionally as this process is a treatment not a coating it won’t come off.  This finish is far superior to zinc plating which, although cheaper, will come off over time and expose the steel to the elements since the zinc is sacrificial.  Zinc coating is prettier though.