17mm Bearing UCFL203 Black Oxide Plated Insert + 2-Bolt Flanged Cast Housing Mounted Bearing17mm Black Oxide Plated Insert Mounted Bearing UCFL203 One Bearing 17mm Black Oxide Plated Insert Mounted Bearing UCFL203, measures an inner diameter of 17mm. UCFL203 Black Oxide Plated Insert Bearing + 2 Bolts Flanged Housing. Black oxide has certain properties and characteristics that makes it ideal for certain applications. It is used to add corrosion resistance and for appearance Mounted Bearings Bolt Size: M10 Basic Load (Cr): 12,800 N Basic Load