Fx Crown!

He mentions the impact barrel but seems to have then edited out a piece of the video. Would have liked to have heard that! 
Sounds like the barrel is fixed by 2 screws from above. 
Not sure about the orings on the liner. Is that to fit a small caliber liner into a larger cal barrel? 
Instead of a complete barrel kit?
Next week will be interesting with all these questions being answered. 
Cant wait for one of you guys to get hold of one.