The product is conpatible with the 92FS and the M9, it is not compatible with the M9A1, which already has a 1913 (picatinny) rail and a flat front on the trigger guard. Beretta describes the differences here:
http://www.beretta.com/en-us/comparison-chart/
The product is compatible with most rail-mounted lasers.
Mark H.
It should fit the Beretta M9, and it will allow use of a laser.