Yamaha M1532 M1524
Program Master Buss Module M-1532
This module came from a working mixer that from a fixed installation. Will make a great replacement or spare for your mixer.
You can go to this Yamaha manual link and download a complete manual to see all of the other features on this channel strip.
http://www2.yamaha.co.jp/manual/pdf/
pa/english/mixers/M1532E.pdf