The 7.5 cm Pak 40 (7,5 cm Panzerabwehrkanone 40) was a German 75 millimetre Anti Tank Gun developed in 1939-1941 and used during WW2. The Pak 40 formed the backbone of German anti-tank guns for the latter part of World War II, mostly in towed form, but also on a number of Tank Destroyers such as the Marder series. Approximately 23,500 Pak 40's were produced.

The Pak 40 was the standard German anti-tank gun until the end of the war, and was supplied by Germany to its allies. Some captured guns were used by the Red Army. After the end of the war the Pak 40 remained in service in several European armies, including Albania, Bulgaria, Czechoslovakia, Finland, Norway, Hungary and Romania.
In the case of the Fins who always had to struggle with the huge amounts of armor the Soviets were throwing at them the Pak 40 was a welcome addition to their forces and was used extremely effectively against the Red Army.

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