There are two versions of this. The -001 version is for the 8551 (N51) and the -002 version is for the 9552 (TP700/720)
System Board, Main
Note: The built-in SCSI controller (-002 only?) includes an active terminator. This terminator automatically works when an external SCSI device is attached.
3550 System Board, Sub
Backup battery looks suspiciously like a CR-2032. Backup Battery, Lithium
Note: When installing a 3.5" drive in a 3550 Expansion Unit, use the hard disk drive slide assembly (FRU 85F0035) supplied with the option. (Ed. a model 95 sled)