There might be two versions of the Ch'ŏnma-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'ŏnma-ho is not related to the Chinese Type 62. Despite its relation to the T-62, the original version of the Ch'ŏnma-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'ŏnma-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'ŏnma-ho I was later upgraded to the II version with a laser rangefinder above the mantlet. According to online sources this Ch'ŏnma-ho was upgraded once again, probably in the mid-1980s, with a 'boom shield'. The Ch'ŏnma-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.