Expand for usb port, supply up to 500mA current per port     
Adopt the second age USB controller       
No external power supply        
Driverless , hot plug& play        
Individual over current protection circuits      
Support USB 1.0/1.1.compatible USB 2.0,full speed up to 480Mbps.    
Support 4 bus-powered downstream ports      
Built - in 3.3 Voltage regulator allows single +5V operating voltage    
Design with super streamline & mini       
Chains up to 127 USB drives        
Size: 140 x 35 x 20 mm(Length x Width x Height)