These Tank Commanders are intended to be mated with the turret/casemate of a tank while in the slicer.
I've a free set of tank parts made by TigerAce1945 and m_Bergman that I've converted, with permission, to have open hatches here.
For a tutorial on how to mate your Commanders with their tanks before printing, please watch this video.
These Commanders are natively scaled at 6mm "heroic" scale. To match a truescale 1:285 vehicle, you will want to scale the Commanders down to 85%. I'd recommend just printing all your vehicles at 1:206ish so they actually match your infantry, though.
To match a 1:100 turret, these STLs should be scaled up to 190% on the X/Y Axis and 200% on the Z Axis.
If you want to mess around with all this before purchasing, a Tank Commander is included in the BG1940 free samples set.
