RackSolutions Relay Rack Shelf - Heavy Duty was designed for 2-post relay racks that need to support heavy duty equipment up to 500 lbs. Created for the largest and heaviest equipment our relay rack shelf is made of solid steel construction and zinc plated finish to be able to support large blade centers such as IBM Dell and HP. In addition our heavy duty relay shelf can support UPS units large drive arrays (SAN & NAS appliances) and large chassis servers. Our 2 post relay rack shelf has a depth of 29.15 inches (740.41 mm) and a weight capacity of 500 lbs (227 kgs) making it perfect for mounting a large variety of electronic equipment on your 2post rack that you might not normally be able to mount. Our 2post relay rack heavy duty shelf will require a 2post conversion bracket for installation which will need to be purchased separately. You can select one based on U-height: (2POST-4UKIT 2POST-5UKIT 2POST-7UKIT).