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