There isn't really anymore info they are called Matrix DMX from china. I can't find a model number... There is one by Optima lighting http://optimalighting.com/MATRIX-DMX-PRO-4-Channel-Double-Output-Dimmer-Pack-4132-prod.htm?category_id=26

The others maybe rip offs of this... Im not sure.

What I've found though is that when i am testing continuity of the DMX line through the dimmer, there are spikes and bleed through from pin 1 to pins 2 and 3 when the dimmer is powered on. That could be normal? I don't know.

I've tested all of the cables involved in the chain and continuity is good.

Using Martin LightJockey 2 with universal dmx interface