A pillow block typically consists of a housing with an integrated anti-friction bearing. Unlike flange blocks or units, a pillow block positions the mounted shaft parallel to the mounting surface and perpendicular to the centerline of the mounting holes. The bearing within a pillow block can feature various types of rolling elements, such as ball, cylindrical roller, spherical roller, tapered roller, or metallic/synthetic bushing, defining its specific type. This distinguishes pillow blocks from "Plummer blocks," which are bearing housings provided without bearings, intended for higher load capacities and separate bearing installation.