... -7 4Noise level:Z1,Z2,Z3,Z4 Stainless steel miniature deep groove ball bearings1.Model:Open,Z,2Z,RS,2RS,RZ ... bearings can be calssfied as “open”,”shielded”,”sealed”.(1) Single-row deep groove ball bearingsThey can sustain radial loads mainly and can ... ,Realistic,Pioneering and Innovative5.Welcome to inquiry . Stainless steel miniature deep groove ball bearings