Insta-Blak 335 is recommended for blackening cold and hot rolled carbon steels, alloy steels, tool steels, as well as cast iron, forged steels and powdered metal. It will even blacken A2 Tool Steel without using a prep (although it may have a small amount of smut). It will not blacken stainless steels. Insta-Blak 335 works well for properly cleaned steel sheets and parts for interior architectural steel finishes.
Insta-Blak 335 is Perfect For:
- Tools/fasteners, firearms, architectural surfaces, and furniture
- Steel sheets and architectural surfaces
- A2 Tool Steel
- Expedited shipping
Insta-Blak 335 represents a major breakthrough in the room temperature blackening of iron and steel. For years, Insta-Blak 333 has been the standard in room temperature blackening. Now, Insta-Blak 335 produces an even darker black finish.


Insta-Blak 335 is recommended for blackening cold and hot rolled carbon steels, alloy steels, tool steels, as well as cast iron, forged steels and powdered metal. It will even blacken A2 Tool Steel without using a prep (although it may have a small amount of smut). It will not blacken stainless steels. Insta-Blak 335 works well for properly cleaned steel sheets and parts for interior architectural steel finishes.
Insta-Blak 335 is Perfect For:
- Tools/fasteners, firearms, architectural surfaces, and furniture
- Steel sheets and architectural surfaces
- A2 Tool Steel
- Expedited shipping