The BT-SV is a Soviet, tier 3, premium light tank. It is currently not available in the in-game store.

This tank, along with the PzKpfw II Ausf. J, MTLS-1G14, and the SU-851 were never introduced, though will likely be introduced at a later date.

The tank has very heavy armour, coupled with sloping, which allows it to resist practically every other tier 3 gun in game, save for a few. The engine is also very powerful, and gives the tank extremly fast acceleration, yet does not turn very well, so attack paths must be chosen well, and lakes and bodies of water should be avoided, while in reality this tank was amphibious, this is not the case in World of Tanks.