Beretta 92F vs. 92FS: What's the Difference?

[Legionnaire]

Easy question, I hope. What's the difference between a Beretta 92F and a 92FS?

Relatedly, what version of the Beretta is current issue for the Marines? Thanks!

 

[Elbeeo]

http://www.thehighroad.org/showthread.php?t=330263

 

[Kurt_D]

As far as issue weapons, I believe the army uses the M9 and the Marines have started issuing the M9A1 (has a rail).