TRIPP LITE's SR18UB premium SmartRack 18U enclosure cabinet is packed with features designed to simplify rack equipment installations and rack equipment maintenance: top and bottom cable routing ports, perforated door and side panels to promote efficient airflow, adjustable vertical mounting rails and more. And as part of the SmartRack family, the SR18UB is compatible with Tripp Lite's extensive range of rackmount accessories, enabling you to customize your solution to meet any requirement. The SR18UB ships fully assembled for quick installation and comes with a 5 yr warranty. br br The SR12UB is compatible with all standard 19 in rack equipment and features front and rear pairs of vertical rails with square mounting holes. The rails are adjustable in qter in increments to accommodate equipment depths from 3 – 32.5 in, ideal for standard server installation. Adjustment is quick and convenient: simply unscrew the rails, slide them to the desired depth and restore the screws. The rails feature square mounting holes and are capable of supporting up to 1000 lb of equipment with included installation hardware. Each rack space within the enclosure is numbered for easy reference. br br To simplify deployment, the SR18UB comes with an accessory caster kit consisting of 4 casters and all required installation hardware. With casters installed, the SR18UB can easily be maneuvered into to desired location, and then secured in place by adjusting the unit's levelers. Note: the casters are intended for minor position adjustments within the final installation area only and are not designed for moving the enclosure over long distances.