Give customers details about the banner image(s) or content on the template.
1. Suitable for black passivation of various zinc plated parts
2. Hexavalent chromium-free and oxidizer-free, high corrosion resistance
3. High impurity tolerance, long service life
4. Uniform color, simple operation
5. Fully pass boiling water test, meet ROHS standard
6. Suitable for rack and barrel plating, same effects on acid and alkaline zinc