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. Custom width, depth and height RIB Series riser bases are also available,