The T-72 is a Soviet-esigned main battle tank that entered production in 1971. It is a further development of T-62 with some features of T-64A (to which it was a parallel design) and has been further developed as the T-90. Chronologically and in design terms it belongs to the same generation of tanks as the US M60 Patton, German Leopard 1 and British Chieftain tank. More recently, the T-72's reputation has suffered following poor combat performance of export models against Western tanks such as the M1 Abrams and Challenger 1 during the first and second Persian Gulf wars. Its losses, however, may have been more a consequence of the fact that most Iraqi T-72 tanks were export models (T-72, T-72M and T-72M1) using low quality ammunition and manned by poorly trained Iraqi tankers.