Twin Pillow Block Linear Ball Bearing IPPSWN32G 2" Open - Precision Plus Self-AligningDouble linear ball bearing pillow block, open shelled, with a 2" inner diameter (ID) self aligning bearing inside an aluminum alloy housing with 2 lubrication ports called "grease zerk fittings" on the side. Interchangeable with industry standards, the bearing has a low coefficient of friction, a heat treated alloy steel shell for durability, and a resin retainer polymer cage to reduce noise. Double size equal to two standard pillow blocks mounted