This is a very scarce and probably a "One of a Kind" prototype, short frame transitional model Luger with a unique reinforced chamber area. These models were used by the Luger factory to develop new designs on a single gun basis like a tool room or concept evaluation style basis, that might evolve into an actual prototype design. This model of pistol has all the attributes of other prototype models in that it has the old style frame, with the flat, double recoil spring, dished toggles with toggle lock, early style fast taper style barrel, flat breechblock, and a totally unmarked safety/frame area. The only markings on the entire pistol are a small number "2" on the underside of the front toggle and a small number "5" inside the rear frame recess. This example has a single unmarked wood base magazine with a nickel plated magazine body. As noted however is the fact that the breech end of the barrel has the reinforced barrel/chamber area in front of the barrel extension. Certainly a very rare and one of a kind Luger that warrants considerably more research.