Beretta 92 series M model....
Beretta USA produced a slim style 92 series 9mmNATO called the M.
It was meant as a compact or plain-clothes version of the milspec M9/92F.
It held a thin 8/9 round magazine but had the same specs as the larger 92F.
Massad Ayoob, gun writer & tactics instructor wrote that the M pistol saw duty use with the US Army CIDC(criminal investigations) & USAF/OSI but was soon replaced by SIG's robust M11 or P228 9mmNATO.
A few NIB & LNIB M series 9mm Beretta 92s are out there. They are rare but a decent sidearm.