Nonmetallic bearings are selected where self-lubrication and low cost are required and where high temperature stability must be maintained. Nonmetallic materials are widely used for bearing because they offer diversified characteristics that can be applied in a wide range of applications. Generally they have lower heat conductivity, in comparison to metals; therefore they are implemented in applications that have a low PV value. Nonmetallic bearing materials include PTFE, nylon, phenolics, fiber-reinforced plastics and other diverse materials, such as wood and glass.