A pillow block (also known as a "plummer block" or "bearing housing"), 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 wide range of dimension series exist to cater for all requirements. Bearing housings are usually made of grey cast iron. However, various grades of metals can be used to manufacture the same, including ductile iron, steel, stainless steel, and various types of thermoplastics and polyethylene-based plastics. The bearing element may be manufactured from 52100 chromium steel alloy (the most common), stainless steel, plastic, or bushing materials such as SAE660 cast bronze, or SAE841 oil impregnated sintered bronze, or synthetic materials.