During the interwar period that followed World War 1 (1914-1918), the 37mm anti-tank gun was a widely-accepted standard caliber of weapon for armor-defeating purposes and went on to be fitted as main armament on tanks of the period as well. In their towed form, the type was used as a line-of-sight field artillery piece with crews lying in wait ready to ambush unsuspecting enemy tanker crews from all angles. The Skoda Works of Czechoslovakia, global leaders in the field of artillery during the period, was responsible for the design of what became the "3.7cm (37mm) KPUV vz. 34" towed Anti-Tank (AT) gun - design work began in 1934 and service entry followed before the end of the year with deliveries continuing into 1939. To Skoda Works, the weapon was known as "Model A3".
From the outset the weapon was developed to penetrate up to 30mm of armor out to 1,100 yards. This was accomplished through an effective overall design as well as a dedicated Armor-Piercing (AP) fixed-shell projectile. The projectiles weighed just over 1lb and were 1.46in in diameter (37.2mm caliber). To keep the system from becoming a one-dimensional battlefield weapon, it was also made to fire a useful High-Explosive (HE) projectile against "soft" targets such as dug-in enemy infantry and light-skinned vehicles (trucks, armored cars etc...). Range with the HE shell was quite good, out to 4,400 yards, which gave the gunnery crew a considerable advantage against emplacements like machine gun nests.
The weapon's arrangement was conventional, made up of a carriage featuring a pair of multi-spoked solid wheels (some forms were noted with having rubber tires). The gun component was fitted atop the split-trail carriage and featured a simple protective shield for the operating crew and a recoil mechanism mounted atop the gun barrel. The wheeled nature of the design, coupled with the towable capability of the carriage, allowed the weapon to be pulled by "beasts-of-burden", crews or vehicles. The breech was a semi-automatic action which allowed a trained crew to fire up to 12 rounds-per-minute. Muzzle velocity reached 2,210 feet-per-second and the barrel assembly measured 4 feet, 10 inches long.
The KPUV vz. 34 was in circulation prior to the war which meant that stocks were captured by the conquering German Army when it began its takeover of Czechoslovakia in 1938. in the German inventory the weapon was redesignated as "3.7cm PaK 34(t)" and some also went on to be used by the newly-founded nation of "Slovakia" which declared its independence from Czechoslovakia in 1939. The weapon's actual wartime service is largely unknown based on available sources - other similar weapons taken on by Slovakia were used in the Slovak Uprising of 1944 so that may be the case with the KPUV vz. 34 system as well. The Slovak Army acquired some 113 examples of the gun.
The KPUV vz. 34 also went on to make up the main gun armament of the LT vz. 34 and LT vz. 35 light tanks (detailed elsewhere on this site) of the pre-World War 2 Czech Army as well as the T-32 (S-I-D) Tank Destroyer vehicle. Specifications and performance of the tank gun version differed slightly from the towed gun form. The 37mm gun caliber form quickly became an obsolete caliber as tank armor began to increase throughout World War 2. Before the end, 75mm and 76.2mm types were the widely-accepted norm.