This Sliding Keyboard Tray features a mouse tray that can be mounted on either side. It also has a palm rest for comfort and support that doubles as a pen storage area. The tray is height adjustable to fit both standard and ergonomic shaped keyboards. Two low-friction ball bearing slides make it easy for your keyboard to be stored away when not in use. It also includes a keyboard clip to ensure your equipment stays in place. 5 Year Warranty!