Hehe yeah, that’s @tremblap 's amp, which is a custom one from what I remember. Huddersfield did some work with Matamp for some audio analysis/testing, and some of the staff got nice custom ones made.
It wasn’t my plan, but really happy with them! They are made of the same stuff as the “body” of the case. A bit tough to screw in as it’s thicker than the screws are long, but the plastic is soft enough to ‘smush’ to make room.
I’m sure it will change too, but quite pleased with the color palette of the modules I have a the moment.