NNF series bearing is a double row full complement cylindrical roller bearing with seal ring and snap ring. It is a full loaded bearing with low speed and heavy load. It is used in hoisting machinery. This kind of bearing is suitable for any work occasion requiring low speed and heavy load. NNF series is the name of SKF, and INA of the same model is SL04 series. (For example, NNF5016 can also be called SL045016).

NCF bearing is a single row full complement cylindrical roller bearing, which is generally used in reducers and mechanical equipment. NCF series is the name of SKF, and INA of the same model is called SL18 series. (For example, NCF3012 can also be called SL183012).