Actually,
this is an official product. TecToy its creator, is the Sega of Brazil.
As for this black version... hmm.. but the blue version is legit. This black one is probably a re-cased hack, but someone will have to dig deep to find out no doubt.
Emulation, knockoffs and hacks obviously don't count as they are illegal. So like Mr. Ksoft said, your 1st consumer portable Mega Drive. The nomad was a Genesis, and was based on the portable Mega Drive of Japan that was only available on commercial plane flights
.