This read-only value identifies the interconnect bay number this adapter connects to in a blade server environment, with -1 meaning it could not be determined or the server isn't a blade environment; when this value is set, cpqNicIfPhysAdapterSlot reflects a mezzanine number and cpqNicIfPhysAdapterPort reflects the switch port number instead. An admin uses this to trace a blade's NIC connection back to the specific interconnect bay in the enclosure. For example, an admin troubleshooting a blade's network connectivity checks this bay number to know exactly which enclosure interconnect module the adapter is physically wired to.