Ceskomoravská Kolben-Danek was determined not to repeat the problems of its earlier Tancík vz. 33 tankette and gave the gunner a turret for better observation and all-around fields of fire for its new AH-IV tankette. It was assembled from a framework of steel "angle iron" beams, to which armor plates between 12 and 6 mm (0.47 and 0.24 in) thick were riveted. The driver sat on the right side using an observation port protected by bulletproof glass and an armored shutter. To his right was a small vision slit. Also to his right, in all models except the Swedish Strv m/37, was a light Zbrojovka Brno ZB vz. 26 or vz. 30 machine gun that was usually locked in place and fired using a Bowden cable. The gunner sat on the left and manned a small turret fitted with a ZB vz. 35 or ZB vz. 37 heavy machine gun in a ball mount. Most of the machine gun's barrel protruded from the mount and was protected by an armored trough. He had a large vision port to the right of the machine gun mount in the turret and a small vision slit on the left side of the superstructure. 3700 rounds were carried for the two machine guns. No radio was fitted.

The 3.468 litres (211.6 cu in), water-cooled, six-cylinder Praga engine produced 55 horsepower (41 kW) at 2500 rpm. It sat in the rear of the fighting compartment and drove the transmission via a drive shaft that ran forward between the driver and commander to the gearbox. Cooling air was designed to draw air in through the commander's and driver's hatches. This had the advantage of rapidly dispersing gun combustion gases when firing, but several disadvantages. The constant draft generated by the engine greatly affected the crew during cold weather, an engine fire would force the crew to evacuate and the engine noise and heat increased crew fatigue. It had a top speed on the road of 45 kilometres per hour (28 mph) and a range between 150 and 170 kilometres (93 and 106 mi). The semi-automatic Praga-Wilson transmission had five forward gears and one reverse gear to drive the forward-mounted drive sprocket. The suspension was a smaller version of that used in the Panzerkampfwagen 38(t). It consisted of four large road wheels per side, each pair mounted on a wheel carrier and sprung by leaf springs. There were two wheel carriers per side. The idler wheel was at the rear and one return roller was fitted. It had a ground pressure of only 0.5 kg/cm2. It could cross a ditch 1.5 metres (4.9 ft) wide, climb an obstacle .5 to .6 metres (1.6 to 2.0 ft) high and ford a stream .8 metres (2.6 ft) deep.

Iran

The AH-IVs were split between the 1st and 2nd Infantry Divisions in service. Nothing more is known of their service or when they were withdrawn.

Romania

The R-1s were assigned to the cavalry brigades, two platoons of two or three tankettes apiece. All eighteen belonging to the Cavalry Corps were grouped into the ad-hoc "Korne Mechanized Detachment" during the opening stages of Operation Barbarossa, but all were out of commission by 1 October. Twenty-nine of the original thirty-five were allocated to the six cavalry divisions (redesignated from brigades on 25 March 1942) that successfully participated in the German 1942 summer offensive, codenamed Case Blue. The four R-1s belonging to the 1st Cavalry Division's 1st Mechanized Squadron had to be set on fire as no fuel was available for them when the division was encircled outside of Stalingrad in November 1942 as part of the Soviet Operation Uranus counter-offensive. The 5th and 8th Cavalry Divisions had lost at least five R-1s during the same time trying to solidify the crumbling Axis defenses after the Soviet breakthroughs. Both divisions supported the Germans as they attempted to relieve the Stalingrad Pocket in Operation Winter Storm, but were shattered when the Soviets counter-attacked the unsuccessful relief effort in late December 1942. Two other cavalry divisions remained in the Kuban bridgehead after the German withdrawal from the Caucasus, but their two remaining serviceable R-1s were withdrawn back to Romania during the spring of 1943 as obsolete. On 30 August 1943 only thirteen R-1s were available, all assigned to the Cavalry Training Center, although this increased by one on inventories dated 25 March and 19 July 1944. Nothing is known of any action involving R-1s during 1944, but eleven reinforced the 2nd Armored Regiment in Czechoslovakia when it reached the front on 26 March 1945. By 24 April the regiment only had one R-1 available, but none were reported as available after that date.

Sweden

The Strv m/37s initially served with the 1st Armored Battalion until the armored brigades began to be formed in 1943—44. Thereafter they served with the infantry regiments I 2, I 9, I 10 and P 1G Armored Company on Gotland. The tankettes remained in service on Gotland up to 1953.

Ethiopia

All twenty arrived in Djibouti on 9 May 1950 after which they were railed to Addis Ababa. They were used until the 1980s when they participated in the fighting against Somalia.