MOISTURE-PROOF: New trend of dc 12 volt moisture-proof muffin fan that designed for high humidity (80%) cooling vent project,verified test up to 4cm water for 4 hours. DUAL BALL BEARING: 92mm fan 12v high cfm small electric fan with long lasting dual ball bearing provides up to 60000 hours over 6 years life. VARIABLE SPEED CONTROLLER: With a 3.3v-12v speed controller small window fan can achieve different airflow (31.8-95.4CFM) and noise level(21-52.5dBA) according to demand. 100V-240V PLUG: Increases the maximum fan speed and enables the fan to be powered through an outlet,just plugging it into the outlet to start the fan. SPECIFICATION: Size: 92x92x38mm;3.62x3.62x1.5inches Dual Ball Bearing Voltage: 3.3-12V Current: 0.12-0.6Amp Air Flow: 31.8-95.4CFM Noise: 21-52.5dBA Connector: DC 5.5x2.1mm Female. DIY COOLING: High airflow 90mm vent fan with double-sided metal grills can be used to cool media cabinet,rv fridge and keep electronics running at their ideal