Those hard plastic cases were rental cases. I know, as I acquired mine from a store that rented out the TG-16, when they were getting rid of stock, and let me have the case and system in it.
What is REALLY rare, that I have NEVER seen outside of the time I saw it for display in that store, was the TG-16 system rental poster. I can't recall how exactly it was worded, but something to the effect of pay X amount of money to rent the system, and get 3 games to rent also. or, it was rent ZX amount of games and get a system rental also. The entire poster was one of those word+picture sentence puzzle things. It ended with the line, "It will [Picture of a guy with a leaf blower blowing leaves] away". It will blow you away. I recall some TG-16 ads used a similar ad style for their magazine ads.
I actually asked TZD about the cases, when they were still around. I can't recall all he told me about them, just, yeah, rental cases, and I think he said they may have been available outside of that, though I am not sure where. I do remember him telling my the TG-16 folks hired a gun case manufacturer to manufacture the cases for the systems.
Mine is hard plastic all around, no foam. I have seen two variations on the molded plastic. Mine has space for a Turbo Booster. I think the other variation I saw lacked that space.
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