This is a representation of a Bitcoin that can be used to house a QR Code or NFC Tag that contains your Bitcoin Address.
This coin has the generally accepted BTC Sign, the year of the publishing of the Genesis Block, as well as a latin phrase that roughly translates to "Equality we can verify."
The back side of the coin has a large recess that can be used to hold any kind of engraving, NFC tag, or QR Code printout that you wish. I would suggest, once you place whatever you wish to keep safe on the back, to seal it with some durable clear epoxy or (if you happen to have it on hand) nice clear nail polish.
Once equipped with your desired address keeping method, the coin becomes an easy way to carry your bitcoins. It can also be used for your cold storage wallet that will be reasonably safe from most methods of damage. Engraving/stamping will be especially safe as it will be mostly fire proof...supposing you purchase it in some kind of metal of course.
Double up on your fiat freedom by purchasing the coin in the precious metal option of silver.
Changes Made: By request, I have increased the diameter of the coin by about 1/3. This should let make the coin allow larger QR codes and NFC Tags to be affixed to the blank side.