UCSF21032S6H1 FYH Stainless Steel Bearing Square Flanged Mounted Bearing Cylindrical bore (with set screws) 2" Inner Diameter UCSF21032S6H1 FYH Stainless Steel heavy duty four-bolt flange unit has a round cartridge on the backside of the flange which allows for precise mounting and alignment, applications are Rotating drum, rotating roller and when precise mounting accuracy is required.