I am building a Tiger I and the drive sproket calls for a poly cap that I do not see one of.
I ran into this with the Pershing kit too.
What is a Poly Cap and where do I find them?
Should be little black polyethylene (hence the name ‘poly’) pieces in a separate baggie. They are used in drive sprockets/props/idlers on the Tamiya kits. Should be tubular and not a “cap” but open on both ends.
The poly-caps are the little vinyl rings on the small un-numbered sprue.
Yea, building M48A3, requires polycaps but dont fit 
are they the small ones or the larger ones on the end of the stick thing?
Small ones go in the roadwheels/sprockets. The long ones are used to hold the two hull halves together, usually at the bow end.
They are really convenient,I wished Dragon used them to
Many times they are in the same plastic envelope as the decals and may be clear or white color making them vanish from sight at times.
Mike T.