Item NO:UER204~UER212UER Standard duty,With cylindrical outer ring and snap ring,Concentric lockingInsert bearing: Gcr15(AISI52100) steel,heat treated,precision ground,raceway superfinished. Steel ball:G10 only. Retainer: Low noise refined cage. Lubricant: Low noise,high speed/load SHELL GADUS S2 V220 2 only. Outer ring with grease groove and holes,at same side of concentric locking collar With anti-rotation pin at opposite side of concentric locking collar Phone: +86-592-580 8851 / +86-592-580 7618Email: sales@ldk-bearing.com ; benjamin@ldk-bearings.com