The fan uses double ball bearings (balls are different from hydraulics and the balls are very durable). The official parameters are as follows: Dimensions: 120*120*25mm Pitch: 10.5cm Rated voltage: 12V Rated current: 0.3A Input power: 3.6W Speed: 0-2500RPM5% 4-wire temperature control Maximum air volume: 89CFM Maximum static pressure: 64Pa Noise: 0-30DB Weight: 120g Fan connector: motherboard standard 4-Pin connector (Requires board support and speed control function, the fan will be quiet under the speed regulation. Otherwise it will always be 2500 rpm at full speed, full speed sound 30DB)