This Multifunction Mobile Stand-Up Computer Desk Work Station combines simple design, solid construction, and multiple surfaces to deliver a cost-effective solution for office and classroom presentation needs. A bottom shelf with 19.75" of clearance offers ample space for PC towers and the height-adjustable second shelf serves as a keyboard tray whether you're sitting or standing. When it’s time to store or use the cart elsewhere, 4 rolling casters with 2 locking brakes make maneuvering quick and easy.