https://www.warhistoryonline.com/guns/firing-the-powerful-german-pak-40-anti-tank_gun-m.html
Firing The Powerful German PAK-40 Anti-Tank Gun! | War History Online
May 6, 2017 - The 75 millimeter Pak 40 anti-tank gun was a German anti-tank gun developed during WWII from 1939-1941. PAK is the abbreviation for "Panzerabwehrkanone."