Abstract: A bearing isolator seal is used to seal the space between the housing and the rotating shaft to prevent contaminants such as abrasive particles, moisture, and corrosive media from entering the bearing. The preferred embodiment consists of a stationary retainer ring with a groove for an O-ring adjacent to a bearing housing, a rotating mating ring with a groove for a second O-ring adjacent to a rotating shaft, and a floating ring made of a material with a low coefficient of friction and a low elastic modulus. The cross-section of the floating ring can be Z-shaped, U-shaped, or V-shaped. A C-shaped locking ring is used as an aid to assemble the aforementioned seal components into a module and is subsequently removed after the seal is installed. Contaminants are stopped at both ends of the floating ring as well as at the O-rings by their spring action. The seal is also designed to release pressure built up in the bearing lubricating system.