Product Detail Providing 1200, 900 and 750 rpm speed settings the supplied Low-Noise, Ultra-Low-Noise Adapters, the NF-P14 FLX can be fine-tuned for superior airflow The latest version of Noctua advanced SCD drive system ensures superb running smoothness by eliminating torque variations and switching noises. Metal reinforcements, SCD2 technology and Noctua premium grade SSO-Bearing guarantee exceptional running smoothness and excellent long-term stability . The "Noctua Ultra Silent 140mm Fan NF-P14 FLX Brown" is best product for you. We recommended Noctua Ultra Silent 140mm Fan NF-P14 FLX Brown