Generally the inner and outer rings made with POM or PA, Cage made with PA66 and the balls made with glass, stainless or ceramic. Material PA have excellent mechanical strength and wearing resistance, PA66 High Precision Plastic Bearings is suitable for manufacturing precision plastic bearings. Plastic bearing made with POM is the most extensive sort of all the plastic bearings. The Density of PA66 plastic bearings is 1.14 g/cm3, Sliding friction coefficient is 0.35-0.42, Short-time highest application temperature is 170℃. PA66 High Precision Plastic Bearings could be used in some alkaline environment but not proper to some acid corrosion environment. With good self-lubrication performance and low friction coefficients, PA66 High Precision Plastic Bearings could be used in precise and high speed application.