Panzer III (Introduction) 

Type: Medium tank

Nationality: Germany

Almost 6000 Panzer III tanks and more than 9 000 other armored vehicles based on the same chassis were built. It remained the standard model of the German Panzerdivisions until 1942. After that, its gun became useless against the better armored allied tanks while its hull was to weak to carry a turret with a heavier gun. The production stopped in August 1943.
Outside the Wehrmacht, the Panzer III was also used by some of Germany's allies: Hungary, Rumania, Bulgaria, Slovakia, Croatia. Even Germany's enemies used it, e.g. Russians and Poles (captured units of course). After the war, Norway and Czechoslakia still made use of some of them.
Other designation(s): Sd.Kfz. 141
Production: 5 500 units

 Panzer III (submersible) 

Type: Amphibious tank

Nationality: Germany

During the preparations for the landing in Britain (Operation Sealion), the Germans converted 160 Panzer III into submersible vehicles. They should be able to leave a landing craft by a depth of 25 feet and continue alone to the beach. They were equiped with a rubber schnorkel, replaced afterwards with a steel one.
They were not used against Britain but exploited their amphibious abitilies while crossing the Bug the day Germany attacked the Soviet Union. It was planned to use them against Malta, but the assault never materialized.
Notice: this model dived to cross water whereas real amphibious tanks remained above surface.
Other designation(s): Panzer III (Tauchfähig)
Production: 160 units

 Panzer III Observation Tank 

Type: Reconnaissance tank

Nationality: Germany

Observation tank for batteries of self-propelled guns. Its gun was replaced by a fake. The weaponry was limited to a MG. Its radio equipment was upgraded to allow it to fulfill its mission. Reinforced armor.
Identification: The MG is located in the middle of the front turret while the fake gun is on the right. The bolted armor plates are clearly visible in the front of the turret and the hull.
Other designation(s): Panzerbeobachtung III

 Panzer III Recovery Tank 

Type: Recovery tank

Nationality: Germany

Conversion of a Panzer III into a recovery vehicle.
Other designation(s): Bergepanzer III; Sd.Kfz. 143
Production: 176 units