Logitech Wireless Mouse M325 - Optical - Wireless - Radio Frequency - USB - Tilt Wheel - 3 Button(s) - Symmetrical Advanced optical tracking - For pinpoint accuracy on a wide range of surfaces. Scroll wheel - With microprecise scroll capability enables easy forward and backward Internet navigation. Programmable buttons - Make it easy to customize the mouse's functions to suit your preferences. Ambidextrous design - Allows easy use with either the left or right hand. Contoured shape - Along with textured rubber grips offers comfortable use.