Ergonomic Industrial Keyboard with built in 51mm Large Trackball with Three Buttons. Oversized Trackball is Ergonomically Sound, and Keyboard utilizes Renowned Cherry Mechanical Key switches with extreme reliability and duty cycle ratings. Used in Work place, Offices or at Home.Features Specificatons:Built-in large size(51mm) Trackball for pointing and software-scrollingAdjustable Tilt Mechanism Scroll-In-Mouse Program Bundled N-key-roll-over Reliable mechanical click key switch ( 20,000,000 life cycles per switch), Supports:-- All MS Windows OS, Apple, SUNLayout - 104/105 keyWeight - 1386gAdjustable tilt mechanism Connections: Single Cable with Dual-Head PS2 Connectors for Keyboard and Mouse. Dimensions: 19.1" Long x 6.8" x 1.3" All Sales Are Final, No Returns No Refunds On Electronic Devices