Beretta 92F (1984) – initially designated 92SB-F, later renamed 92F. Evolved from the Model 92SB during American XM9 trials, with a slightly reshaped grip and trigger-guard, also a different finish. The barrel bore and chamber are chrome-plated.
Beretta 92FS (1989) – a minor modification of the Model 92F, with an enlarged hammer pin head which prevents the slide from flying back in the case of breakage. Presently, all US M9 pistols are modified to 92FS standard.
http://world.guns.ru/handguns/hg07-e.htm
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Got an italian 92F in '86 for CC and duty - GREAT gun.
Bought an M9 the other day, just because.
The M9 has some hybrid polymer parts that the 92F didn't (trigger, mag release, mainspring housing, guide rod)
Enjoy!