Bearing SSO2. •Ultra-Low-Noise Adaptor (U.L.N.A.). •3:4-Pin Adaptor. Rotational Speed (+/- 10%) 1200 RPM. Rotational Speed with L.N.A. (+/- 10%) 900 RPM. Rotational Speed with U.L.N.A. (+/- 10%) 700 RPM.
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