... 2RS ZV21. material:chrome steel2. ISO9001:2000 certificate3. High Speed ZV2 GRADE4. Inseparable design5. More than 15 years Bearing ... 61800 61900 R series,F seriesRings MaterialStainless steel-440C,304 316 ,Chrome steel-GCr15, high Carbon steel-GCR11Cages Materialsteel ... Italy,Spain ,Poland,Romania,Bulgaria,South Africa, Middel East and Southeast Asia. We adopt modern scientific management system with ...