Just a few years before the official end to the unofficial Cold War, Poland’s military decided to modify its license built T-72M1s. The idea was to incorporate as many locally produced upgrades as possible. So many items were changed that the PT-91 Twardy (tough, strong) is almost a totally different tank from the T-72; engine, transmission, auto-loader, targeting system, etc.
U.S. Army photo by Sergeant Andres Chandler, 13JUN2020.
Drawsko Pomorskie Training Area, Poland, June 2020.
USA photo by Sergeant Andres Chandler, 13JUN2020.
USA photo by Sergeant Andres Chandler, 13JUN2020.
NATO video of PT-91 live-fire during wargame in Latvia, April 2020:
Canadian Forces photo.
Polish Hussars PT-91 during Assurance wargame in Latvia, 26JUL2018.
Michigan Army National Guard photo by Captain Tyler Piper, 06JUN2018.
Michigan Army National Guard photo by Specialist Alan Prince , 06JUN2018.
Bemowo Piskie Training Area, Poland, June 2018.
Michigan Army National Guard photo by Specialist Robert Douglas, 15JUN2018.
USA photo by Specialist Hubert D. Delany the Third, 06JUN2018.
USA photo by Specialist Hubert D. Delany the Third, 06JUN2018.
Polish PT-91 in Latvia, at Camp Ādaži, 11MAR2018. Canadian Forces photo by Corporal Jean-Roch Chabot.
Canadian Forces photo by Corporal Jean-Roch Chabot.
In Latvia, February 2018, NATO wargame Reassurance. A PT-91 arrives for ‘decontamination’.
Canadian Forces photo by Corporal Jean-Roch Chabot.
A Slovenian soldier checks for ‘contamination’ of PT-91’s tracks/road wheels.
Canadian Forces photo by Corporal Jean-Roch Chabot.
Polish PT-91 about to get ‘decontaminated’ during CBRN (Chemical Biological Radiological Nuclear) training in Latvia. Back in the Cold War, and through the 1990s, we called it NBC (nuclear Biological Chemical) training.
Camp Ādaži, Latvia. Canadian Forces photo by Master Corporal Gerald Cormier, 02OCT2017.
Canadian Forces video by Master Corporal Brandon O’Connell, Polish PT-91 during NATO wargame in Latvia, 2017:
Camp Ādaži, Latvia. Canadian Forces photo by Master Corporal Gerald Cormier, 02OCT2017.
U.S. Army photo by Charles Rosemond, 15JUN2017.
Adazi, Latvia, during NATO Saber Strike wargame, June 2017.
U.S. Army photo by Specialist Brandon Best, 04JUN2017.
U.S. Marine Corps photo by First Lieutenant Kristine Racicot.
Since the 1990s, many new versions of the PT-91 battle-tank have come out, with different designations and names. There’s even recovery vehicles, engineer vehicles, bridgelayers and self propelled artillery based on the PT-91. Besides Poland, Georgia, India and Malaysia use some type of PT-91 variant.
Soviet era Armor in use by NATO: 
POLAND
NATO: 
POLAND SUKHOI 22
Polish designed MTLB engineer vehicle known as Opal or TRI, June 2017.
A PT-91(improved T-72) based WZT-3M recovery vehicle on public display in 2016 (note the Christian priest wearing the tanker helmet).
WZT-3M, June 2017.
The PT-91 is Poland’s version of a modernized T-72, this pic was taken in June 2018 during NATO’s Puma 2 Exercise-Saber Strike.