Nuoxi S500 5 Fans Blue LED Laptop Cooling Pad with Stand +2 USB Port for 12"~19" 2 USB port,extra 1 x USB 2.0 Port There are 2 buttons to control the wind speed,one button controls the biggest fan,another button controls other 4pcs fans.Then you can control the wind speed by yourself. Suitable for 12~19inch laptops.NOTES:While the cooler pad is a little smaller than the laptop,it doesn't effect the effect of heat dissipation. Light weight and thin design. 5 kinds stand could be adjusted,can protect cervical health.