They say NCV because this kind of plaque can only be played, not cashed. I believe that they were made for promotional use, but I'm not sure they were ever actually distributed to players. Seller says he got them from vault storage. There are other denominations as well. They were unknown to the hobby (at least to me) till this quantity of unused plaques showed up on eBay.

They are nice items if you collect Nevada plaques or no cash value chips. It's hard to price these things though as not everyone collects them. Some of his auctions have a "make an offer" option where you can tell him what you would pay and he says yes or no.

I have the 1000 and it's a nice serialized B&G product, although pretty small.