Nope, that's for the SA-08 in 28 gauge. The SA-08 in 12 gauge takes Browning Invector (
not Plus), Mossberg Accu-Choke and Win-Choke.
http://www.weatherby.com/products/shotguns/choke-tube-guide.html
To the OP:
I do not use those chokes on a SA-08, as I shoot Mossberg for turkey, but I wouldn't over think this too much. A choke is a tapered constriction of a shotgun barrel's bore at the muzzle, so what are we talking about here? A tube getting smaller at the end, it's not rocket science, lol.
Way too much is made about turkey chokes. People are striving for the tightest pattern humanly possible (1 million pellets in a 2 inch circle) but when they miss they're mystified. Hmmm, too tight? Yup! As long as you get a decent pattern (no gaping holes) and you know where it's shooting (high/low/left/right) at 20 and 40 yards (max suggested shot distance) then you'll be fine.
P.S. Check out oldgobbler(dot)com.