Twin Roller Pillow Block - Linear Bearing TWN-12-OPN 3/4" Shaft DiameterTwin (TWN) Roller Bearing Pillow Block designed for a 3 4" diameter shaft covers twice the space on a linear shaft compared to a single roller pillow block (SPB). The twin pillow block features two sets of 3 opposing roller bearings mounted in a larger twin housing with an open bearing style, as if two Single Roller Pillow Blocks (SPB) were fused together. This differs from Double (DPB) Pillow Blocks, which also have two sets of 3 rollers, but the DPB