The NF-S12A case fans marked the third generation of "159Noctua951 's classic S12 series, which has received more than 250 awards and recommendations in the international trade press. By refined blade geometry with anti-stall Knobs and modern AAO-frames (short for Advanced Acoustic Optimisation) of NF-S12A achieved compared to its renowned predecessors greater by up to 8% efficiency (output / noise). The FLX version allowed on the Low-Noise Adapters three speed settings (1200/900/700 rpm) and offers full flexibility in fine-tuning between maximum performance and virtually silent operation. Its excellent smoothness, the SSO2 reference-class warehouse and Noctua s proven premium quality make the NF-S12A to a fine choice for noise-optimized case cooling.