A polish 9mm semi-automatic handgun manufactured from 1935 to 1945.
Designed in 1930 by weapon innovator Piotr Wilniewczyc, with the help of Jan Skrzypiński, the Vis (latin for "force", originally called WiS as an acronym of the creators' names, also known as Model 35) was based on the american Colt M1911, but had several technical differences which improved it's accuracy and stability, gave it good ergonomics and a firm grip, while keeping it reliable after over 6000 shots. It was widely considered one of the best firearms of the period today.
It was originally produced in the Radom Arms Factory. After the successful invasion of Poland in World War II, the germans continued it's production, but moved part of the assembly over to a factory in Austria (and finally the entire process in 1944) fearing that the polish underground resistance could smuggle the Radom produce. Actually they made their own from smuggled spare parts and widely used them during the Warsaw Uprising of 1944. After Poland came under soviet dominance the production of the Vis was halted and they were replaced by greatly inferior russian TT-33's.
Though a rarity, they are still prized by collectors to this day.