not sure what that thing is screwed into the front, only guess is that it was for a goose neck of sorts for miking the thing up.
the footswitch ?
the strange thing about this amp is without the footswitch in, both channels are one.. so you can turn up the gain on the second channel and mix the two.. this was apparently marshalls first attempt at a combo amp. its the non-valve equivalent of the 4210. owner made some mods to it, has some peavey balanced output thing on the back and a strange power adapter inside it. will snap pics.
