unknown pieces coming with my die sets

[jollyroger]

my boxes of RCBS dies came with a couple little cardboard disks; I hate to be such an ignoramous, but do they have any purpose?

 

[Six Star]

I often wondered what they were, too...I'm pretty sure that they are some sort of dehumidifying material, like the little silica gel packets.
Any other ideas anyone?

 

[bigbull]

That is what they are, corrossion inhibitors.
bigbull