World s Biggest notebook cooler that supports up to 20 Notebook PCs. Height & Angle Adjusting Risers for User"s Convenience. USB Powered and Multiple USB ports. USB Cable Compartment for Great Portability. Premium Aluminum Surface. Rubber Grip Strip to prevent notebook PCs from sliding. Dual Centrifugal fans with large vents for maximum performance. Zalman s Unique and Sleek Design. BLACK.