Trilogy gemini intercom 8 chnannel AEB board (to connect to 8 panes / 4wire))

full working order

price is for 1 card

From trilogy

 700-26-20 Audio Expansion Board - 8 Channel The most common option board supports a mix of 8 panels and / or 4-wire audio circuits. The 8 ports may be freely configured one-by-one in software and there are no hardware changes required