I've used to mount almost everything to these: pedals, wireless units, PS3, PoE-adapters... You can fit almost anything in these. I've been lucky that often mounting holes in equipment have had exact match, but you can also easily zip tie things on to these. My only "complaint" is that there isn't a deeper version (that I know...) of this. Something like 40-50cm with maybe ears to attach it to back rails. Would be nice for some non-standard equipment like power packs or just organizing cables.