Logitech V250 Cordless Optical Mouse & Number Pad Kit Logitech V250 Cordless Optical Mouse &amp; Number Pad Kit for Notebooks General Features: Logitech V250 Cordless Optical Mouse Black and Silver 3-button, wheel mouse design All-Terrain Optical sensor Wireless RF technology via USB receiver Power saving On/Off switch Logitech V250 Cordless Number Pad Black and Silver Wireless RF technology via USB receiver 18-keys Three (3) calculator function buttons