Strong 1/8 steel construction supports up to 500lbs Rack Mount Shelves - Server Racks (4 Post) Works with square, round, or threaded holes Optional Straps, Anti-Slip Mats for securing equipment Material: Steel Package Contents: Universal 19 Heavy Duty Rack Mount Shelf 4 x Rack Brackets Instructions Screws Cage-nuts Nuts Material: Steel Product Type: Rack Shelf Product Type: Rack Shelf Manufacturer Part Number: 1USHL-116 Form Factor: External Form Factor: External Manufacturer: Innovation First, Inc Product Name: Universal Heavy Duty Rack Mount Shelf Rack Width: 19 Rack Height: 1U Brand Name: Innovation Rack Width: 19 Rack Height: 1U Brand Name: Innovation Maximum Weight Capacity: 500 lb