In the older Nortel price books, the AC is listed as RO (reference only) and the only "orderable" part was the NTBB80AAAB. Both are called MSPEC III. I can find ton of AC on the refurb market and NTBB80AAAB is still available new. I have a BCM 3.7 (purchased new at the time) and want to replace one or both PECs. I have a No Resource when accessing voice mail otherwise the BCM and all it's phones are working fine. Any help would be great.