Lenovo System x PDU Technical Reference page 29

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Mounting in EIA (U space) of rack
Mounting the DPI PDU (39Y8951) in the U space of a rack requires the use of the
horizontal mounting bracket, shipped as part of the PDU accessory kit, see the
Accessory Kit section for additional information.
Two PDUs will fit in 1U of rack space as seen in figure 8.
Figure 8: DPI PDU horizontal U Space mounting in rack
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