ULTRA- PORTABLE2.4G Wireless optical pen mouse,(5.7 x 0.6 x 1 )inch mini size, just like a pen. It fits in your pocket, take it to your class, meeting and wherever you go. You can use a wireless mouse anywhere you like. DPI ADJUSTABLE 800, 1200, 1600 DPI levels adjustment-500/1000, help you find a proper 'speed'. The grip is very natural and you can position your arm close to the body, or even on the body for comfort. POWER SAVING Come with USB receiver, up to 33ft effective distance. Powered by one 1 x AAA battery(not included),plug and play.The auto sleeps function, no worry about waste of your battery. ERGONOMIC DESIGNFits comfortably on your hand, pen-shaped, perfect for handwriting input and graphics design.Designed with a wheel for page turning during PPT presentation. BEST GIFTCompatible with: Windows ME/ NT/2000/XP/Vista/7/8 ,Android ,Mac, OC etc. A prefect present for teachers,professors,classmates,colleaguefriends and leaders.