Whatever the were, they worked. I was able to remove the drums by hand with no tugging or cursing. They just came off nicely. Looks like the anti-seize is the way to go.

The ancient set of original Minifins I have don't have any such pieces (and neither do the newer versions I've ever seen).  Probably something added by a PO...  So its up to you to (re?)invent a substitute. 

I just use a smear of anti-seize where the alloy sits on the axle flange... shouldn't need too much "beating" to release... more tapping with rubber hammer.

BTW What's salt??

Cheers, Ian

My measurements are correct. Digital calipers can go way down the decimal scale. Yes, about the thickness of heavy bond paper.

They may not be needed. However, curiosity requires at least a small effort to find out if they are needed and where to get them.

My guess would be to prevent the drums locking to the hubs through galvanic corrosion, Can't see wheres there any place to beat on them, like standard drums, without min fins breaking. like apple trees, drums on cars in road salt states need a bit of a beating.

Good thing it wasn't written .00375 milimetres! (Nice catch, Doug.)

Can you check your measurement again?  The value you listed is about the thickness of heavy bond paper.  I cannot imagine how you measured out to 5 decimal places.  I assume the decimal point is in the wrong place.  

I'm no expert, but I have a hard time thinking this part is necessary.

But then, I'm either right, or that should tell you something about how I maintain my cars..

I have the ally MiniFin rear drums. There is a thin (.00375" wall) plastic/delrin spacer inserted into the center of the drum that fits around the circumference of the bearing cap. These are worn away and I cannot find them listed anywhere. Can anyone help?