One would want to protect there credit and debit cards from being scanned in your wallet from thieves. Such technology has existed for a few years now. You can be anywhere and someone goes by you with the right tool which you would not see and it will scan the cards in your wallet/purse if not protected to block such. I have had one of those card holders for about 2-3 years now. You can purchase such for about 6-10 dollars in most stores anymore which would be still alot cheaper than buying insulbright and making one.