John, you will need a cylinder choke tube to shoot these slugs, available here >>> amazon.com/Carlsons-16611-Beretta-Benelli-Cylinder-725/dp/B000KT1D0C

John, G2 Research recommends a Cylinder Choke. The included Improved Cylinder Choke (the one with 4 notches) is not recommended by G2 Research. I would adhere to their recommendation of Cylinder Choke **ONLY** - walmart.com/ip/Carlson-s-12-Gauge-Beretta-Benelli-Mobil-Flush-Mount-Cylinder-Choke-Tube-16611/23332419 --- Cheers and stay safe!

It says on g2 research website "Not for use with Choke
Cylinder Bore ONLY!"
But a cylinder bore choke offers no restriction of the barrel, and trying to shoot without a choke screwed in can damage the barrel threading, this gun will shoot the Rip round as long as you have in the correct choke installed (Cylinder Bore)
"This shotgun
Includes a full choke set (Full, Modified, & Improved Cylinder)"
But no cylinder bore (no restriction) you'd have to buy that separately in stock here
shopbenelli.com/choke-tubes/BSF-12CHK