... all kinds of ball bearing,welcome to inquiry DEEP GROOVE BALL BEARINGSDeep Groove Ball Bearing is the most commonly used rolling bearing ... pump, agricultural machinery and fabrics machine, etc.Characteristic of deep groove ball bearing:1. Seal form: open style, Z, ZZ, RS ... : 59 - 63HRCExplanation:Z represents that one-side of the deep groove ball bearing is mental dust cover, and ZZ represents that ...