Is that a Czech "Alfa Project" revolver? They didn't seem to get much traction in the US, so are they going with Rock Island to sell their guns?
9mm revolvers became a thing in the 1980's (I think the Israelis tried out the idea in the early fifties, but never went into production), when the European cops began to realize that their 32 automatics weren't cutting it any more. US cops nearly all carried revolvers then, and their advice to the Europeans was to get revolvers in 38 or 357. The Europeans weren't keen on either round, so S&W and Ruger both rolled out 9mm revolvers to capitalize on the idea in a cartridge that was more familiar in Europe. The Europeans nearly all went with 9mm automatics - I think Spain was an exception, and Manhurin in France made super-expensive revolvers in 357. After that, the 9mm revolver idea faded, but somebody comes out with a new one now and then.
To me, the idea would make more sense if they made the cylinder the same length as a 9x19mm round, with a frame to match, but they never do. They always take a 38/357 and give it a 9mm cylinder. I don't see the point in that.
9mm is not much longer than 38 S&W. Heck, for all I know, it may be a bit shorter. Try to imagine this gun:
https://www.gunbroker.com/item/887224993
beefed up to handle 9mm. (And minus the grip safety, plus a standard J-frame grip.) THAT makes sense to me, although it may be an idea whose time has already gone by, what with the low price of polymer pocket-sized 9mm automatics.
I await the response of those who will tell me it can't be done. Sure, we can make a J-frame 357 Magnum, but we can't do this. If you say so, fine.