COMBATEX Parkerized Sling Swivels have a durable, non-reflective, flat dark gray finish that is very rust and abrasion resistant. The Parkerized finish protects steel from corrosion and increases wear resistance.
It is recommended to apply a light coat of gun oil to the swivels. Parkerized steel surfaces will absorb and hold oil for maximum protection from the elements.
The time consuming process of Parkerizing steel has been in use since World War 2 and is still used on military firearms, parts and vehicle components.