The Firearms Blog indicates that Recover has released a replacement grip for the Beretta 92 that adds an accessory rail to the firearm without any gunsmithing. You may remember that this company had previously released a model for the Colt 1911.
As you can see from the photo, the grip doesn't just replace the side plates, but it also covers the trigger guard and the bottom of the slide--thus, the accessory rail.
I bought one for the 1911. Although I haven't gone shooting with it, I installed it on the pistol to see how it worked. The fit and finish was good, and as far as I could tell, the accessory rail seemed solid. It seemed a good way to update an older firearm so it can mount a flashlight and/or laser. If the model for the Beretta is as good as the one for the 1911, I think it would be a worthwhile upgrade for someone wanting an accessory rail.
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