This is an example of a very rare and seldom encountered WWII Soviet mortar. The 50 mm Model 1940 (50Krh/40) was produced in large numbers, and it was a popular and effective weapon that could be easily and inexpensively manufactured, as its base plate and bipod were simple steel stamping. In operation, the intention was to have the barrel at one of two known firing angles, with fine adjustment of range via a set of vents controlled by a collar at the base of the tube. The bipod integrates a screw-operated elevation adjustment and a screw-operated leveling mechanism.