Timesaving and practical, the Raised Floor Enclosure Systemª consists of 2-1/2-inch high riser bases, which provide the ability to perform field rough-in procedures prior to the arrival of the racks and enclosures. Also handy as a lower ca…ble chase for passing cables between racks in multi-bay applications, riser bases feature 1/8-inch thick fully welded construction and an attractive black powder coat finish. Riser bases feature knockouts for passing cables between joined riser bases. Riser feet bring riser bases to a 12-inch height for use with raised floors. Raised floor support angles support floor tiles when used with riser bases and feet.