Slewing bearings can accommodate axial, radial and moment loads acting singly or in combination and in any direction. They are not mounted in housing or on a shaft, but directly to a seating surface. The inner and outer rings are supplied with mounting holes. Both rings may have integral gears. They are also referred to as slewing rings and tabletop bearings. Slewing ring bearings can perform oscillating (slewing) as well as rotating movements. They may be used without gears or with internal or external gears.
four-point contact ball slewing bearing 
