Tripp Lite's SmartRack SRSHELF2PDP is a 2U cantilever mount fixed shelf. Cantilever shelf supports monitors and other equipment with a 27 kgs (60 lbs) capacity. Shelf is compatible with 2 or 4 post rack enclosure cabinets. The SRSHELF2PDP is 21 inches in depth but can use two shelves back to back to create a deep fixed shelf in 2POST racks.