Finger Handhold 4D USB Mini Trackball Mouse Mice Thumb Control For PC Computer This is a portable finger hand-held 4D USB mini trackball mouse with off-table design for free and comfortable operation. It is ideal for laptop users. Features: 1.It can be operated in various ways to ensure long-term use without harm to wrist or muscle 2.No limitation of operational space 3.Avoid sitting closely to the monitor and reduce the harm of radiation and eye fatigue 4.Plug and play ,no software required 5.Fits left and right handed users 6.Compatible with Win7,Win8 ME/ XP/ NT 7.Unit Dimensions: 3.152.051.97 inches (85.25cm) 8.USB Cord Length: 73inches (186cm) 9.Color: Black How To Use: 1.Put your index or middle finger into the hole of this mouse. 2.Control the track ball for moving cursor and press the right and left button with your thumb 3.When using Drag and Go" function, press the button in the hole of the mouse that has the same function as the left button of the common mouse 4.Use the left button to lock the screen and then you can control the track ball to roll your screen freely Package included: 1 x Handhold 4D USB Mini Trackball Mouse"