really, trumpeter/someone really should spend some time on a T-72A early or T-72M1 and eventually, the long awaited T-72 ural......

I was going to post about it just being another name for the T-10 but then realised the engine deck is different...

Not familiar with the JS-5... did it go into production before being replaced by the T54/55 series or was it an interim/ prototype? Off to the reference library for me.

The USSR at the time was producing both heavy tanks (IS series) and mediums (T-44, 54, 55 etc), prior to going for the dual MBT line which they found could carry just as powerful a main gun but 20 tons lighter (cheap and cheerful T-55, T62 line or expensive composite armour, gas turbine, autoloader line as in the T-64). The heavies were based on the IS-2 line, then IS-3 a couple of hundred IS-4, the IS-5, IS-6 and IS-7 were various protypes only, the only other which went into production was IS-8, which Kruschev renamed the T-10 after de-Stalinisation of the USSR.

Thanks, Eoin, I guessed that it was something like that and appreciate the info!