Along with Anti-Stall Knobs that reduce flow separation in medium- to high-impedance situations, NF-S12A has AAO frames featuring integrated anti-vibration pads as well as Stepped Inlet Design and Inner Surface Microstructures. Respectively, NF-S12A FLX and NF-S12A ULN provide 1,200/900/700 rpm and 800/600 rpm settings. Model NF-S12A PWM comes with NE-FD1 IC for automatic speed control via 4-pin fan headers and Low-Noise-Adaptor to reduce max speed during PWM control from 1,200 to 900 rpm.
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