This is a very rare item which was made in the late 1970s. It appears in the WEM leaflet dated July 1978.
It’s a combined 4 channel mixer and Echo unit. It was made in two versions, one with reverb and one without.
You can see more details in the WEM leaflet via this link :- WEM July 1978 leaflet.
Many thanks to Alberto Zioli for permission to use his pics.
Alberto runs Zioli Guitars and you can see more info about Alberto and Zioli Guitars on his Facebook page :-
The pictures of this next example come courtesy of Chris from Vintage Vinyl –