The LX Wall Mount Keyboard Arm from Ergotron helps you to position your keyboard for maximum comfort and productivity. It attaches to sturdy vertical surfaces or wall tracks via a bracket (97-091, sold separately), while providing vertical and side-to-side motion. Constant Force lift-and-pivot motion technology allows you to position your keyboard with just a light touch. The arm extends the keyboard tray up to 35" and you can also adjust height up to 13". It folds straight up at 90° to protrude just 3.5" from the wall. The ergonomic back-tilt keyboard tray ensures wrists remain in a neutral position during data entry to avoid repetitive-stress injuries while increasing comfort and productivity. Fasteners for direct attachment to wood and metal studs or concrete surface are not included.