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A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is 19 inches (
482.6 mm) wide. The 19 inch dimension
Some telecommunications and networking equipment is available in a narrower 10" format with the same unit-height as a standard 19"-rack1.
Racks are vertically divided into regions,
44.45 mm (
1.75 in) in height1 (1U).