The Rohrbaugh R9 is a semi-automatic pocket pistol chambered in 9mm. Rohrbaugh Firearms is a gun manufacturer that specializes in pocket pistols.
The R9 has a locked-breech design where the barrel and slide are locked together until a round is fired and then the move in tandem. The slide rides back, the barrel tilts and the recoil is absorbed by the slide instead of the frame.
Its internal components are constructed primarily from stainless steel and 7057 aircraft aluminum alloy, which puts its weight at slightly less than a pound. The R9 has a double-action only trigger, so the R9 omits the use of a safety.