An M60 Army tank on the Axel Artificial Reef off Bayhead, New Jersey, USA. The M60 Patton main battle tank is now primarily found in US Reserve and National Guard units, but served as the primary US main battle tank for two decades prior to the introduction of the M1. Developed from the M48 Patton series, the M60 was fitted with a 105mm main gun and manned by a four-man crew. Criticized for its high profile and limited cross-country mobility, this durable tank proved reliable and underwent many updates over its service life. Initially produced in 1960, over 15,000 M60s were built by Chrysler and first saw service in 1961. Production ended in 1983, but 5,400 older models were converted to the M60A3 variant ending in 1990.