http://www.finn.no/finn/viewimage/;pdc=1130351095797?finnkode=6239949&reference=623/994/9_1263726219.jpg&adheading=GJ%D8R+ET+KUPP+%28Onyko+forsterkeren+og+h%F8ytalere+er+solgt%29

I have called the seller and he does not know any more than me.
It has been on his attic for 15 years and he tried it and knows it works.