My Parker D grade was M/F so I though I'd open up the Full a bit. Well, a brain fart latter the left barrel was a tight IC - .018, or close to LM. The right was actually .022, or a tight Mod. I might have to change a couple other guns to this because I'm really starting to like it. I think LM/IM would be some just about perfect chokes if I could only have one gun. Heaven forbid.