I know KG claims the off-black Gun-Kote 2300 product was certified for Seal Team guns. A 500 hour salt spray test was passed. I've also recently seen that one of the ceramic coating products, Ceracoat, I think, had passed a 1000 hour salt spray test. I believe it was compared with Gun-kote and Durakote in the same test and outperformed them, but being a thicker coating, it isn't really an entirely fair comparison. Interestingly, the ceramic coating is harder rather than softer, but supposidly resists abrasion best of the three.
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