It's a choke, but different - Rossi Choke Tube for Circuit Judge

The choke threads on fine and looks like it'll do the job, but the "rifling" is more like channels similar to an M-16 star chamber and there are no wrench slots. The channels do not reverse twist; they are parallel to the tube. Though the choke is not as expected or as depicted, I believe this one will tighten the spread better than reverse rifling, but may impede some shot that bounces into the beginning of the channel walls. The lack of wrench slots is easily overcone by using the channels to tighten with Leatherman pliers inserted to the end or with some manner of makeshift tool. Perhaps the reverse twist was implemented to prevent the choke from walking out? Honestly, I've never seen an OEM choke, so maybe what I have is typical, but every forum I've read on the Rossi Circuit Judge choke is that it is supposed to be reverse rifling, not straight channels.