The T-34 medium tank is one of the most-produced and longest-lived tanks of all time.
Identification of T-34 variants can be complicated. Turret castings and superficial details, and equipment differed between factories. New features were added in the middle of production runs or retrofitted to older tanks. Knocked-out tanks were rebuilt, sometimes with the addition of newer-model equipment and even new turrets. Some tanks also had applique armor made of scrap steel of varying thickness, welded on to the hull and turret these tanks are called s ekranami (with screens), although this was never an official designation for any T-34 variant.