There might be two versions of the Ch'onma-ho 1: the copy of the Syrian T-62 in the late 1970s, and an original copy exported by the Soviet Union which may be the T-62D. The Ch'onma-ho is not related to the Chinese Type 62. Despite its relation to the T-62, the original version of the Ch'onma-ho had thinner armour and was consequently lighter. This version of the tank has two distinctive bolts on the bottom portion of the upper glacis plate. The Ch'onma-ho I name was also given (at least by the West and South Korean white papers) to the imported T-62, which was later slightly upgraded to the IM version. Although no dates are available, the Ch'onma-ho I was later upgraded to the II version with a laser rangefinder above the mantlet. According to online sources this Ch'onma-ho was upgraded once again, probably in the mid-1980s, with a 'boom shield'. The Ch'onma-ho III might have also seen an armour upgrade with the addition of full-hull skirting and a new thermal shroud for the original 115 mm main gun.
The most modern Ch'onma-ho tanks seem to be the IV and V versions. The Ch'onma-ho IV is fitted with what resemble EDZ light explosive reactive armour bricks. Judging by photographs, these are mounted specifically on the turret side, with at least eight bricks per side. The Ch'onma-ho IV is reported to be upgraded with new side-mounted smoke launchers. North Korea is rumored to have received a few examples of the T-72s after 1992, and possibly a single T-90S main battle tank in August 2001. Any conclusion regarding whether the Ch'onma-ho has been upgraded to the standards of either the T-72 or the T-90S would be highly speculative at this point.
Around 90% of the Ch'onma-ho is indigenously produced. There is evidence, however, that North Korea has purchased entire engines, or engine components, from Slovakia. Furthermore, it is thought that ceramic components, possibly for an upgraded armour scheme, are from foreign sources, as well as fire control components. It is not clear how much is indigenously produced in regards to the different variants of the Ch'onma-ho. The figure of 90% could have changed considerably between the original Ch'onma-ho I and the Ch'onma-ho V, although it should be kept into consideration that many of the major features are probably purchased from abroad – especially for the upgrades of the tanks. It is not clear how much North Korea can afford on producing on its own, or how much it can afford to import for that matter. It is thought that North Korea is considerably low on resources, especially money, and this belief has been perpetuated after North Korea's nuclear test incidents in 2006. It is possible that Russia is supplying North Korea with several components for North Korea's tank projects which include the Ch'onma-ho and quite possibly the M-2002, although no hard evidence can support this claim.
In August 2010 North Korean media revealed images of its new main battle tank the Pokpung-ho (also known as the M-2002), which had been rumoured to have been under development since the early 1990s and to have undergone performance trials in 2002. While precise details of its capabilities remain unclear, the Pokpung-ho appears to be simply a further improvement of the Ch'onma-ho. The news concerning North Korea's future main battle tank has certainly driven South Korea to look for outlets for their own national tank programs, including the future South Korean Main Battle Tank, the K2.