Noctua's NF-A12X25 series of fans took Noctua almost five years to develop. They even outperform many 140mm fans! Noctua NF-A12x25 FLX Premium Quality Quiet 120mm Fan. Providing 2000, 1700 and 1350 rpm speed settings via the supplied Low-Noise and Ultra-Low-Noise Adapters, the NF-A12x25 FLX (Flexibility) can be fine-tuned for superior airflow or maximum quietness.
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