PT-91 Twardy is a Polish main battle tank (MBT), a Polish version of the Soviet T-72 tank.

PT-91 Twardy was design by OBRUM (Ośrodek Badawczo-Rozwojowy Urządzeń Mechanicznych – EN: Research and Development Centre for Mechanical Appliances) and manufactured by Bumar Łabędy.

Bumar Łabędy is part of the Polish military consortium Bumar Group.

PT-91 entered service with the Polish Army starting with 1995. A total of 281 PT-91 tanks were built.

With a mass of 45.9 tonnes, PT-91 has an overall length of 9.67 with the barrel, while the chassis measures 6.95 m in length.

It has a width of 3.59 m, a height of 2.19 m, and a ground clearance of 0.395 m.

PT-91 Twardy has a crew of three (3) persons.

PT-91 has composite armor, with the front and sides made of laminated armor.

The front, side, and top armor is covered by Erawa-1/Erawa-2 ERA modules.

As the main armament, PT-91 uses a 125 mm 2A46 (D-81TM) gun with 42 rounds is also fitted with one 12.7 mm NSVT heavy machine gun with 300 rounds and one 7.62 mm PKT coaxial general-purpose machine gun with 2,000 rounds.

Powered by an 850 hp (634 kW) PZL-Wola S-12U diesel engine coupled to a manual transmission, PT-91 has a power-to-weight ratio of 18.5 hp/tonne (13.8 kW/tonne)

PT-91 tank uses a torsion bar suspension and with a fuel capacity of 1,000 liters has an operational range of 650 km.

With extra fuel tanks, the operational range increases to 700 km.

PT-91 Twardy can reach a maximum speed of 60 km/h.