This is a Goldstar Mini Modem that is brand new in the box.  It can run off of a 9-volt battery or the AC adapter supplied.

This is 2,400 baud and uses a serial interface.  It includes the case, serial 24 to 9 pin adapter, the telephone cord a telephone splitter, the 9 volt DC adapter a hanger, the software and manual. It includes the original battery that expired in 1994 but I highly doubt that it is still working.

This is an absolutely new condition with the exception of the box which has a lot of dings and the Styrofoam, but it is untested so is being sold as is.