Icon list question

[TDR]

JUst been going through all the various bits that come with the game..
In a file called "WINSPMBT_MasterIconList.txt" on many vehicles the turret 'graphic' has a value of 6976, eg icon #4 M113. I though this was the MG but 6976 ends up as a hull graphic.

Is this a special turret type code for vehicle that don't have turret graphics but have turret ability for their weapons?

Thanks
(Just waiting for WinSPWW2)