Retainers keep the balls evenly spaced around the raceway preventing ball to ball contact and thus allowing higher speeds. They also help to retain grease around the balls and raceways. For greater accuracy and to prevent any additional friction, it is important that the retainer is not allowed too much radial movement. To achieve this, the retainer is guided by either the balls or one of the rings. See the sections below for information on how each cage type is guided. 

RETAINERS-Freerun standard bearing retainers are made from cold rolled carbon steel however, in cases of corrosive environment, misalignment,or high speed operation, stainless steel, or phenolic resins will be used upon request. 

For specific applications,Please contact Freerun Bearing Co.,ltd Concerning availability and compatibility of different retainers type.