Twin Pillow Block - Linear Roller Bearing MTWN-20-OPN-S for a 20mm Shaft, 2 ScrapersTwin (TWN) Cam Roller Bearing Pillow Block with copper scrapers for a 20mm diameter shaft. Twin roller pillow blocks cover twice the space on a linear shaft as a single roller pillow block. The twin pillow block has two sets of 3 opposing roller bearings mounted onto this double sized twin housing, as if two Single Roller Pillow Blocks (SPB) were fused together to make a much larger bearing. This differs from the Double (DPB) Pillow Blocks which also