... :1.Ball bearing.Roller bearing. hub bearing 2.material,steel GCR - 15 3.Certificate: ISO 9001:2000 4.Hardness ... 62Deep groove ball bearings description:1. Material: Gcr15 Chrome steel, Stainless steel or Carbon steel2. Brand: TINMY3. High quality with ... ,51200,51300,51400,DAC,BC, etc.Ring MaterialChrome Steel ,Carbon steel,Stainless steelTolerance gradeGB/T307.1-205ID Size10mm-280mmQuality standardISO ...