1/2" Bearing UCP201-8 Black Oxide Plated Insert + Pillow Block Cast Housing Mounted BearingUCP201 8 Black Oxide Plated Insert Pillow Block Bearing Set Screw Type High Center Height 1 2" inch Inner Diameter UCP201 8 Black Oxide Plated Insert Pillow Block Bearing, UCP201 8 Black is Set Screw Type High Center Height, Inner Diameter is 1 2" inch. Black oxide has certain properties and characteristics that makes it ideal for certain applications. It is used to add corrosion resistance and for appearance. UCP201 8 Black Oxide Plated Insert Pillow