Single "Raybar" bead on my 20 gauge Ithaca. I swapped the original out for the one that was on my Dad's old full choke 12 gauge barrel when he passed. We hunted together a lot, and he would have wanted me to have his pet shotgun, but my sister took all his guns and sold them for pennies on the dollar before I could get it. Luckily she left the barrel, so at least I can carry a part of his old shotgun.
Bob