Up for sale is a DOD 240 Resistance Mixer, a simple, no-nonsense 4-input passive mixer in the classic gray enclosure.

Plug up to four sources into the side jacks, set the level for each channel with its own knob, and take a single blended signal out of the output jack on the front. It’s a handy tool for combining multiple guitars, keyboards, drum machines, synths, or effects loops into one amp or input. Because it’s passive, there’s no battery and no power supply to deal with.