surface treatment for material products

Normal surface treatment for material products.
As hydrulics fittings, adapters, the most common surface treatment is Zinc plated.
Under the Prop 65, REACH, RosH and so on ,Cr6+ free zinc plated is the most popular, that can be meet more than 120 hours salt spray test.
Of course we can choose other finishments for 560 hrs or more.