Important Note on Surface Appearance of Spare Parts
You may notice a brown, black, or even blueish substance or coating on some of our metal spare parts. This is not rust.
What you’re seeing is a surface treatment called blackening (also known as chemical black oxide coating). This is a chemical process used to darken the surface of metal parts, typically to black, brown, or blue shades.
Far from being a defect, this treatment offers several important benefits:
Corrosion resistance: The blackened surface adds a layer of protection against rust.
Reduced light reflection: Helpful in applications where glare reduction is useful.
Preserved dimensions: Unlike paint or plating, blackening doesn’t change the part’s size or fit.
Improved appearance: Gives the parts a clean, professional finish.
In short, the dark surface on these parts is intentional and functional—not a sign of damage or wear. It actually helps the part last longer, especially in harsh or humid environments.
