12 mm x 28 mm x 8 mm NACHI 6001 deep groove ball bearings

NACHI Bearing offers a 12 mm x 28 mm x 8 mm NACHI 6001 deep groove ball bearings selection of Genuine NACHI Bearing at Wholesale 12 mm x 28 mm x 8 mm Prices. We Timken BEARINGS INDUSTRY are a 12 mm x 28 mm x 8 mm NACHI 6001 deep groove ball bearings Certified 81 mm Oil level, min. Parts Retailer

What is 6001 bearing cross reference？