[IDGAF27]

I know it is verrrrry old thread, but it was brought up in other very recent thread, so let me chip in about those "discs".

any junk yard, dissmantler, salvage yard glues them on once guarantee to the part is given. most of , those sellers, parts are sold with 30 to 90 day guarantee.
In order to protect them self from scammers that takes good parts( lets say) from seller and just before guarantee expires brings some core crap for refund.
Those discs just aluminum stamp glued to the case.
Yes, I am talking from my experience. Placed many discs like that on parts sold.