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19 inch rack

Design Specification for 19 inch Racks

When designing a rack system, one of the most important factors to take into account, is whether the racks you select will fit the servers you need. The Ausrack Plus range of cabinets are designed toSSI specifications for Computer Server Cabinets & Enclosures. This is an independent specification that has been endorsed by all the major server and network equipment brands.


A rack's mounting fixture consists of two parallel metal strips (referred to as "rails") standing vertically. The rails are separated by a gap of 17.72 inches (450 mm), and are a minimum of 0.657" (16.7mm) wide giving an overall rack width of 19 inches (482.6 mm).

The rails have holes in them at regular intervals, with both rails matching, so that each hole is part of a horizontal pair with a centre-to-centre distance of 18.3 inches (465 mm). The holes in the rails are arranged vertically in repeating sets of three, with centre-to-centre separations of 0.5 inch (12.7 mm), 0.625 inch (15.875 mm), 0.625 inch (15.875 mm). The hole pattern thus repeats every 1.75 inches (44.45 mm).

Racks are divided into regions, 1.75 inches in height, within which there are three complete hole pairs in a vertically symmetric pattern, the holes being centred 0.25 inch (6.4 mm), 0.875 inch (22.2 mm), and 1.5 inch (38.1 mm) from the top or bottom of the region. Such a region is commonly known as an "RU" or "U", for rack unit or unit respectively.

The Ausrack uses plain square mounting holes as these allow boltless mounting of some equipment, and can be adapted for use with bolts by the use of cage nuts. The rails are made of steel of 2 mm thickness for strength. All Ausrack Plus and Lite range include 4 rails as standard, 2 at the front and two at the rear.

For an easy to read summary of this information, please see the pdf on rack specifications or visit our specialised division B&R Data Systems.

For more information on the type of rack available, see our 19 inch rack products page or select a rack from the table below: -

Selection Chart

Model Number Height
Request Quote
AF24U606 24 1202 600 600
AF24U609 24 1202 600 900
AF24U611 24 1202 600 1100
AF40U606 40 1913 600 600
AF40U609 40 1913 600 900
AF40U611 40 1913 600 1100
AF45U606 45 2135 600 600
AF45U609 45 2135 600 900
AF45U611 45 2135 600 1100
AF40U809 40 1913 800 900
AF40U811 40 1913 800 1100
AF45U809 45 2135 800 900
AF45U811 45 2135 800 1100



Server rack - Ausrack Plus Frame
Material - steel
Top showing cable access through stiffening Bend back cable entries Frame showing bottom cable access Ausrack branding Feet adjustable from inside the enclosure (screw head shown) Rails RU marked