The 125mm Anti Tank gun was developed in by the Petrov Design Bureau in two variants, the D-13 towed and SD-13 Self Propelled. The SD-13 was the basis of the 2A45M "Sprut-B" smoothbore anti tank gun which entered service in the late 1980s. It has a crew of 7 men and it uses the same ammunition as the T-62, T-72, T-80 and T-90 tanks.