The RX21-25SFD mobile cabinet is ruggedly constructed of 16-ga. CRS and include heavy-duty casters. Equipped with a front pair of 11-gauge CRS adjustable mounting rails tapped 10-32 on standard E.I.A. 5/8"- 5/8"-1/2" spacing. Optional RR21 rear mounting rails are available for additional support. Front-to-rear mounting rail supports have slotted cutouts to easily adjust rail depth and to provide open raceways for containing vertically run wire and cable. The RX21 features the additional benefit of having the supports positioned 19" apart to accept standard panel width accessories mounted in vertical orientation. Cabinet is 25 1/2" deep and has a vertical panel space height of 36 7/8" It features one pair of recessed, hinged, and rubber-padded steel grips on each side (four total) for transport convenience.