GB 308-2002 Chinese standard ISO9001:2000 International standard 1. Material: GCr15 (E52100/100Cr6) 2. Different grades: G10--G1000 3. SIZE:3.175mm~150.000mm 4. Hardness: HRC59~64. 5. Origin: CHINA 6. Applied in high-speed and low-noise special bearing,motor bearing, household electric applicance bearing, thrust bearing, rotary bearing and rolling mill bearing