The Passive Mult is a two channel multiple.

The Passive Mult is a two channel multiple. It can behave as a dual one to three mult, or in a single channel/normalized one to six configuration. Since the device is passive it can also be used as a three to one, or six to one mixer!

This module requires no power, so all you have to do is build up the kit and install it in your enclosure with the supplied 3mm screws.

https://4mscompany.com/p.php?p=962&c=11