Those are really cool. Little known fact is UHC made them, and then they were sent to MGC in Japan. They were never as popular compared to the S&W 645 series, ironically compared to real life.
UHC produced the most amount of guns for Japan, compared to any other non-Japanese company. From the TK VP70, Marukoshi Super-9, and most of the spring guns for Maruzen/Crossman and Tokyo Marui Spring pistol line up.
An interesting company that most people thought just made junk, we're outsourced to make a lot of guns in the old days for big players in airsoft.