... . Ceramic bearings, of long life, with high precision. 1) Ceramic bearings: Special 639 ceramic bearings of high precision.2) OEM: We can provide OEM ... outside size: Standard size.7) Precision rating: P0, P6, P5, P4, P2.8) Logo: We can mould, print or laser your logo ... ) Packaging: Wooden package, carton package. Special 639 ceramic bearings of high precision