Lenovo ThinkStation P7 Manual page 15

FLEX bay M.2 kit installation
The front access FLEX bay is located on the front of the P7, as shown here:
The FLEX bay can hold a single M.2 drive, which can be installed as long as the
internal 3.5" bay M.2 drive kits are not in use. The M.2 drive is mounted into a
FLEX bay carrier, which is then inserted into the FLEX bay slot.
FLEX Bay Carrier FLEX Bay Slot
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