R4ZZ (I.D.=1/4", O.D.=5/8", Thickness=0.196")r4-2z bearings are shielded on BOTH SIDES to keep lubricant inChromium Steel long-life bearings, smooth and low noiseABEC Tolerance 1 (P0), Z2 Noise Level for most general useStatic load rating of 615 newtons and dynamic load rating of 1480 newtons.
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