Matias Optimizer Keyboard High-Quality Rubber Dome Keyswitches Provide a Quiet Tactile Feel  Tab Key on the Number Pad Allows One-Handed Number Entry Into Forms, Spreadsheets, and Accounting Software   Optimize Key Provides Short-Cut Access to Frequently Used Commands  Standard USB Keyboard Connection   No Drivers Needed Compatable With Windows and Mac users  Dimensions Inches: 18.7" x 6.4" x 1.6" / 2 lbs