How to Use Ultra-Blak 404
Ultra-Blak 404 oxidizing salts can be used to give a variety of metals—particularly cast iron—deep black finishes. Add 5–25 pounds of Ultra-Blak 404 per week per 100-gallon production tank.
Use Ultra-Blak 404 to:
- Blacken cast iron, malleable iron, and many steels;
- Achieve rich black finishes on workpieces, including all castings
- Work with oxidizing salts rather than liquid solutions
- Work with a hot-temperature blackening process
Ultra-Blak 404 oxidizing salts are used to blacken cast iron, malleable iron, and some mild low-carbon steels with a deep, rich black finish. Also available in liquid form with our Ultra-Blak 404L.

Corrosive

Health Hazard

Irritant

Oxidizer
How to Use Ultra-Blak 404
Ultra-Blak 404 oxidizing salts can be used to give a variety of metals—particularly cast iron—deep black finishes. Add 5–25 pounds of Ultra-Blak 404 per week per 100-gallon production tank.
Use Ultra-Blak 404 to:
- Blacken cast iron, malleable iron, and many steels;
- Achieve rich black finishes on workpieces, including all castings
- Work with oxidizing salts rather than liquid solutions
- Work with a hot-temperature blackening process