Fujitsu PRIMECENTER M1 User Manual page 35

Preparing to install rack components
The Height Unit (HU)
The unit of measurement used in the PRIMECENTER M1 19-inch rack is the
height unit (HU). One height unit comprises a 3-hole section in the front area
and mounting area (starts and ends with a narrow metal bar) and corresponds
to 44.45 mm or 1 ¾ inches.
The height units are numbered consecutively in ascending order from 1
upwards on each vertical support upright.
1 HE
1 HE
1 HU
Figure 10: Height unit (HU)
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