Super silent 12cm fan with S-FLOW blades supplying 30% more airflow than a standard fan at the same speed. The greater performance combined with PWM automatic speed control allows the fan noise to be kept to a minimum. The Apache fan creates more focused airflow providing blind-spot cooling, which makes it an ideal solution for a case or heatsink fan. HDB (Hydro Dynamic) bearings extend fan life and further enhance noise reduction. IP54 military standard ensures the fan is dust and moisture resistant. Its powerful, quiet and tough! PWM is a widely available feature on all current Intel and AMD platform based motherboards. It is more accurate than voltage regulation, energy saving and a fully automatic way of controlling the fan speed. PWM provides ultra quiet acoustics during normal PC use and high performance cooling under high system load. The Optional Akasa AK-CB002 cable adapter can provide the system with two additional PWM connectors if needed. Specification:- Super silent APACHE fans in camouflage colours- S-FLOW fan blade design delivers 30% higher airflow- IP-54 military standard moisture and dust protection- Super silent with PWM auto speed control- Hydro Dynamic Bearing extends fan life up to 50,000 hours- Dimension 120 X 120 X 25mm- Bearing HDB (Hydro Dynamic Bearing)- Speed 600 -1300 RPM- Max airflow 57.53 CFM (97.74 m3/h)- Sound level 6.9 -16.05 dB(A)- Max static air pressure 2.64 mm-H2O- Rated voltage 12V- Connector PWM-4pin