Dick' s sporting goods and Bass Pro both sell the Mossberg extra full choke for the 500. I bought mine online when they werent available in the store.

I know there are other brands as well but I have no experience with them.

Truthfully, I dont know the lingo as this is my first experience with turkey hunting and this choke.

I am shooting consistently slightly low and to the right but it is consistent and it is a nice pattern. I am going to adjust my shooting to compensate this year and better prepare next year.

I wont shoot over 30 yards so that I am confident I am taking a good shot.

I am only using 2 3/4 winchester high velocity turkey loads.