The two machine guns pictured above were very common for the average Polish soldier. The uppermost is the 9 mm Sten MkIII. This weapon was incredibly cheap and easy to produce. The parts were mainly stamped and welded. By using parts that were common and easy to assemble, production of this weapon could be farmed out to cottage type industries away from the main industrial targets of England. The MkIII could generally not be repaired when broken. The cheap cost of the weapon generally made it more economical to throw away when malfunctioning, rather than attempt to repair it. The inexpensive nature of this weapon, however, did precipitate a number of problems in functionality and reliability.
The second weapon is the venerable Thompson Sub Machine Gun borne of World War One trench warfare. These guns were made of mostly machine milled parts which required great skill and time for production. Both added to the comparatively great cost. I have heard estimates that the average Thompson cost approximately $500.00 to produce at the time, compared to the $12 of the Sten Mk III. The Thompson was well liked by its Polish owners. Before Normandy there was a push to turn in the tried and true Thompsons and replace them with the Sten whose 9mm ammo would be widely available when they reached the continent. Various veteran accounts, however, detail the great lengths the troops went through to retain their beloved Thompsons and the subsequent stopping power that the .45 ACP round exhibited.