... our factories. We are the professional manufacturer of producing the bearings. Please look at the information about our factories. Built: ... ABEC3,ABEC5, Noise level:Z2,Z3,Z4 According to ISO9001Products: Deep groove ball bearings, roller bearings.Materials: chrome steel (Gcr15)Technology: low vibration, low ... 607-6020,625-6220, 6300-6320,6800-6815, 6900-6915. bearings, ball bearings, JUF bearings