1-1/2" Bearing UCP208-24 Black Oxide Plated Insert + Pillow Block Cast Housing UnitUCP208 24 Black Oxide Plated Insert Pillow Block Bearing Set Screw Type High Center Height 1 1 2" inch Inner Diameter UCP208 24 Pillow Block Bearing, UCP208 24 is Set Screw Type High Center Height, Inner Diameter is 1 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.. UCP208 24 Black Oxide Plated Insert Bearing + Pillow block