These ball bearings are made with high quality 52100 high carbon steel. The balls themselves are grade 10 and the grease that comes already equipped is Chevron SRI 2. Our standard for radial ball bearing quality requirements is ABEC-1 and the standard internal clearance is C3.
If the bearing selected is equipped with rubber seals (2RS), it has molded seals made from Buna-N and bonded to a steel inserts for strength. Max operating temperature for our sealed bearings is 240F. This type of seal makes contact with the inner ring of the bearing to protect it from contaminated environments better tan the bearings equipped with only a metal shield.
If the bearing selected is equipped with metal shields (ZZ), it has non-removable, no contact steel shield. These shields enable you to run the bearings at a higher temperature and since the inner race has no contact with the shield there is no impact on torque or speed. The downside to this type of enclosure is the lack of sealing protection from outside elements.
This bearing is sometimes marked with one of the following markings: 6200-ZZ, 62002Z, 62002Z, 62002Z, 200KDD, 1200FF, 77200, 6200ZZ, 200SFF, 200PP, 77500, 6200ZZ, 6200ZZ, 62002Z, 6200ZZ