My brother used a pattern master in his sbe2, and I use a wad wizard(same design the co-owners split up years ago) in my sx2, I love my supreme which is the same as a extended PM. Great chokes, also they now make ported or unported so its your choice really. Where to buy, some online stores will ship them up others wont ship gun parts, I ordered my Wad wizard from canadianwaterfowlers proshop in alberta, my brother bought his when we were down in the states.