Appears to be New!
Fast Mac 33.6 External Modem, Model FMACV.34 (MV.34EM) by Boca Research (I think) appears to be new. Included in the original box are the modem, new power adapter, serial cable - DB-25 to mini-DIN 8, phone cable and an unopened package containing the manual, MacComCenter manual and software and other literature.
AC adapter appears to be not working. It will still be included in case you can repair it. Modem does power on with a similar borrowed power adapter. Tested to power on only as I do not have telephone service capable of dial-up.