Manufacturer : Noctua. Item model number : NF-A4X10 5V PWM. Premium quiet fan, 40x40x10 mm, 5V, 4-pin PWM, max. 5000 RPM, max. 19.6 dB(A), >150,000 h MTTF. Includes anti-vibration mounts, fan screws, extension cable and OmniJoin adaptor set for connecting the fan to proprietary fan headers.
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