The Soviet spritepack adds 16 more Soviet sprites in the game.
8 New Tanks:

• BT-5
  
• BT-7
  
• T-28
  
• T-34
  
• T-44
  
• KV-1
  
• KV-2
  

• IS-2
  5 New Aircraft:

• Mig-3

• Mig-9

• Lagg-3

• Yak-4

• Sukhoi SU-2
  3 New Ships:

• Gangut-class Battleship

• Kirov-class Heavy Cruiser

• Leningrad-class Destroyer