Prison cells are usually about 6 by 8 feet in size with steel or brick walls and one solid or barred door that locks from the outside. Many modern prison cells are pre-cast. Solid doors may have a window that allows the prisoner to be observed from the outside. Furnishings and fixtures inside the cell are constructed so that they cannot be easily broken and are anchored to the walls or floor. Stainless steel lavatories and commodes are also used. This prevents vandalism or the making of weapons.
There are a number of prison and prison cell configurations, from simple police station holding cells to massive cell blocks in larger correctional facilities.