A pillow block is a pedestal used to provide support for a rotating shaft with the help of compatible bearings & various accessories. Housing material for a pillow block is typically made of cast iron or cast steel. A pillow block may contain a bearing with one of several types of rolling elements, including ball, cylindrical roller, spherical roller, tapered roller, or metallic or synthetic bushing. The type of rolling element defines the type of pillow block. These differ from "plumber blocks" which are bearing housings supplied without any bearings and are usually meant for higher load ratings and a separately installed bearing.Pillow block housings are used to give support when a shaft is turning. With a pillow block, the shaft is parallel to the mounting surface and lies in a perpendicular direction along the centre line of the holes which contain the bolts. This arrangement is different from the one that applies with flange units and flanged blocks.