The shallow depth of the SR45UBSD is an ideal cabinet for shallow-depth audio/video equipment, smaller equipment installs or areas with limited floor space. It houses 3000 lb of standard 19-inch rack equipment in 45U. Its front and rear pairs of vertical rails have square mounting holes that are adjustable in quarter-inch increments from 4 to 27 inches. Adjustment is quick and an easy-view depth index ensures consistent rail placement without requiring time-consuming measurements. Each rack space within the enclosure is numbered for ready reference.