HP Wireless Optical Comfort Mouse Stay Connected: Advanced 2.4 GHz wireless technology for less interference and longer range of operation to work anywhere Get Comfort: Symmetric sculpted design and rubber sides provide comfortable and secure grip for left or right hand use. Get Convenience: The micro-receiver is so small you can leave it plugged in your desktop, notebook or store it inside the mouse. Travel with Confidence: Optical sensor with adjustable sensitivity (1000 CPI default, 1750 CPI max) works on many surfaces Be Productive: 3 buttons including a smooth scroll wheel with middle rubber trim for great control scrolling up and down