Specifications: Material Aluminum & ABS Size of fan 60mm*60mm*10mm Speed of fan 2500 rpm Most noise 25dBA Rated voltage DC 5V Dimension 300mm*230mm*13.8mm Air Flow 28CFM Power consumption < 0.9 W Rated current: < 180 mA Color Options Black or white Function options 4 ports Hub or all in one reader or both   Description：       Slim and smart design of the cooling pad system  with large, high-performance and extra quiet 3 fans built-in which absolutely  helps to dissipate the heat-air away from underneath the notebook computer for cooling down the overall temperature of your system    Extremely heavy-duty construction of the cooling pad to afford any weight or pressure put-on    Power supply supported easily by the plug-and-play USB connection as a self-power mode Convenient reliable and comfortable to carry   No need for any installation   Compatible with any notebook computers   4 ports USB high-speed hub 480 Mbps (NEC)   USB hub all in one card reader   Adjustable height with two nails