Expert Sleepers Tiny MIDI Breakout

This is just an adapter from bare pins to 3.5mm sockets on a plate. There is nothing inherently MIDI about it except of course if you connect to pins, you can use it for TRS 3.5mm MIDI, as expected.

You have to read the instructions very carefully to connect it correctly.

In addition, the instructions say you do not need to connect the sleeve pin which does work for me, but only when connecting to powered devices. To make it work with my unpowered (aka "MIDI powered") Quad MIDI Thru box, I had to write messages to Os on Mod Wiggler and he got back to me confirming my suspicion that actually the sleeve pin SHOULD be connected to a ground (in my case on the back of the ES-9 which I am using it with. This and a few other things make this item feel more DIY than most other modules.