MOISTURE-PROOF: 120mm 5v blower fan with moisture-proof technology designed for normal humidity or outdoor area exhaust cooling. Verified test immersed into 4cm water for 4 hours under 70% humidity. SPECIFICATION: The usb blower exhaust cooling fan is 120x120x32mm(4.72x4.72x1.26inch) current:0.3a-1.2a speed:1300rpm-2000rpm±10% airflow 10cfm -21.87cfm ±10% noise level: 45-53dBA. SPEED CONTROLLER: 5v usb blower fan with stepless speed controller,you can easily optimize fan speed for various applications (low 1300rpm to high speed 2000rpm while noise level from 45-53dBA accordingly). NOISE LEVEL: This 120mm high speed blower fan with very powerful airflow and also will be noisy,if running at maximum speed,the noise level is 53dBA (like a stand pedestal fan working) WIDE APPLICATION: The AC-powered blower fan can be widely used to cool various electronics and components,like rv refrigerator,inflatables,av receiver media cabinet,xbox playstation,wifi router,car audio amp,car seat