Features Scroll - effortless scrolling on web pages and large documents. Just press and hold the center button for 3 seconds to activate scrolling, click any button to exit scroll mode. Drag Lock - lets you drag and drop without holding down a button -the center button, when clicked once, tells the system to select and hold the object until another button is clicked which releases the object. Self-Cleaning - If the ball begins to feel rough after some use, spin the ball very fast in several directions. This will usually eject any dirt from the suface of the rollers. If using the USB interface (CST1350), plug the trackball into any avail USB port on your computer. Drivers will load automatically on most operating systems. If you wish to use the PS2 port, First, turn the system power OFF. plug the USB cable into the green USB to PS2 adapter and then plug that into the PS2 mouse port on your systems. White Box includes trackball, green PS2 adapter, quick start instructions and CD (User Guide). AAC, AADL, ATL, Mouse, Trackball Model CST1350SA M/D 2016.12.07