NGC Premium 2 1/2” Double Pocket Coin Flips. PVC-freeP.V.C. and chemically inert, containing no oils. Made from Archival Coin Safe Polyethylene Terephthalate [P.E.T.]. Cardboard inserts are not included—50 Flips Per Pack.
“Numismatic Guaranty Company (NGC) is an international third-party coin grading and certification service based in Sarasota, Florida. It has certified more than 50 million coins. NGC certification involves authentication, grading, attribution, and encapsulation in clear plastic holders. NGC is a Certified Collectibles Group (CCG) member, which owns six collectible certification services. NGC has been the official grading service of the American Numismatic Association (ANA) since 1995 and the Professional Numismatists Guild (PNG) since 2004” - Wikipedia