A slewing ring bearing has rolling elements designed to create a reactive moment within the bearing's dimensions envelope, to oppose applied (overturning) moment load. This makes it practical to use one bearing instead of two, reducing the height required for an application and often improving performance.

In addition to saving space, a designer can use a slewing ring bearing to simplify a drive system by incorporating gear teeth on the inner or outer race. These gear details can take on many styles and features: Fellows stubs, full-depth involutes, straight or helical, hardened or unhardened, ground or unground. Whatever its style, the success of a slewing ring gear depends on four factors: gear static strength, resistance to pitting, gear fatigue, and gear/pinion interfaces (or mesh).