Fabarm threaded barrel?

[MackDaddy]

I recently purchased a Fabarm Martial 14" shotgun off these forums and the end of the barrel is threaded, it currently has a ring screwed on it but what's the use for this? What could be attached to it? Here's a picture of the tip;

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[Oddbawl]

That's for the FLAMETHROWER! That's for chokes innit? I bet that's where a factory muzzle break would fit. The Shooting edge has 'em for fifty bucks or so on the Fabarm price list. How do you like it? I'm on the fence between that and an 18.5" Benelli Nova.

 

[redleg]

There are a set of external choke tubes available as well as a muzzle break.