... 9001 certified 3.Low noise,Stable in chemical 2013 New Taper Roller Bearings Material: chrome steel STEEL NO.COMPONENTCSiMnCrMoPS ... steel compare to same standard code: ChinaISOAISIDINJISSKFGCr15693/XVII52100100Cr6SUJ2SKF3Series: 24x41x12.50 (Upper 22.5x41x12.5mm, Lower 24x41x12.5mm) ; Knuckle ... Precision Tolerance: ABEC-1 (P0), ABEC-3 (P6), ABE C-5(P5)4) Noise Level: Z2V1, Z3V2 , Z4V3Detailed size ...