https://www.legacy-collectibles.com/...ger-14961.html
3/25/21 - This is a nice example of a very rare Mauser training Luger. The chamber is marked "Ub" for "Ubungswaffe" or "drill practice weapon". The general consensus among collectors is that these guns were put together from scrap parts and used by the Mauser factory to train employees on how to shoot the luger properly. They are very rare. The gun is all matching, but most parts have been re-numbered by the factory to match. There are unit markings on the front strap - we are not sure of the meaning. It has retained about 70% of its original finish. The straps are bare. There is minor wear on the side plate and high edges of the slide and frame. Thinning on the left side of the frame. Comes with excellent wood grips and a mismatched period-correct magazine. The bore is near-mint.