The Smart-AVI SM-RACK SmartRack is a 1U rack-mountable shelf that allows for small devices such as extenders, splitters, and switches to be mounted in all 2-post and 4-post 19" server racks. Compatible with virtually all SmartAVI products, the SmartRack organizes and secures devices to the server rack. The SM-RACK 1U Universal Half Rack Shelf System Includes the SmartRack Shelf, 2 slotted mounting brackets and hardware.