It's the latest "cost-reducing" version of Polyvox console, sold around '89-'90 here in Brazil.
The first version ('84) was exactly the same american "Vader" console with a little NTSC -> PAL-M conversion board added. There are versions with internal power supply and without difficulty switches.
Even Polyvox became pirate after release games not Atari/Activision, like Frogger, Popeye, Spacemaster X-7 (Space Tunnel), Dishaster (Mr. Chin), I Want my Mommy (Apples and Dolls).
At the time, assembled computers (and VGs) weren't allowed to be imported at all. But parts were actually encouraged to be imported. Polyvox officially imported "parts" to "assemble" consoles and cartridges.
Actually, boards came completely assembled (soldering and stuff). Polyvox's work was enclose them in cases, attach labels when necessary, put them in boxes and sell...
Yes, but Polyvox (actually, Gradiente, owner of the Polyvox brand) moved to NES fast enough to continue on VG industry.
It was officially released. I had a friend that owned one at the time! I played on it.
Nowadays, TomBrazil has one. And I played on this one too...