Phosphate coatings appear light gray to black depending on the process used. Phosphate is
a excellent base for paint, and when when combined with a class 2 oil coating, it has good
||Zinc Phosphate base.
||Manganese phosphate base.
| Class 1
||Supplementary preservative treatment or coating, as specified.
| Class 2
||Supplementary treatment with lubricating oil conforming to MIL-L-3150
| Class 3
||No supplementary treatment
| Class 4
||Chemically converted (may be dyed to color as specified). With no
supplementary coating, or supplementary coating