Plain bearings, also called journal bearings, are cylindrical-shaped components with tubular inner surfaces that fit around shafts to facilitate sliding, rotating, and oscillating movement. Dry-run plastic sleeve bearings are lightweight and suitable for fast, high-load, and low-friction operations. Maintenance-free metallic and multi-layered sleeve bearings increase slide performance with an embedded, solid lubricant that's self-applying and never requires maintenance. Lubricated metallic sleeve bearings come pre-applied with grease or oil to minimize friction and vibration. The flanged versions of these sleeve bearings have a protruding lip on one end that's used as a thrust surface or to support installation. Thrust washers are thin, disk-shaped components that fit between bearings and stationary surfaces along a shaft to support axial and thrust movement. Clip bearings fit into holes in metal plates where shafts run through to prevent friction and provide wear resistance. Mounted plain bearings have a housing to ease installation and provide additional support for the bearing.