... material:bearing steel,GCR15 hardness:59-63HRC 16001 2rs low noise deep groove ball bearing detail description:1 ... 4) Shield / Closure: Plain (Open), Z, ZZ, RS, 2RS, 2ZR, 2Z. 5) Vibration and Noisy level: Z1, Z2, ... or other famous brand (SKF, NSK, HCH, KG, KOYO brand, etc.) 3. The company promises: 1) Our ... to establish friendly relations of cooperation. 16001 2rs low noise deep groove ball bearing