Models: Sk8, Sk10, Sk13, Sk16, Sk30,Sk35. Bore Sizes: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 15mm, 17mm, 20mm. Corrosion Defense. Material: Bearing Steel. Cnc-machined Housing with 0.005mm Concentricity Tolerance Prevents Harmonic Resonance in High-rpm Systems.
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