Some chippers call them chokens, Wayne. The are made by Chipco... I believe the Protec series. Not popular and not too durable in the machines. I believe the only other Nevada casino to use them was Ballys, Las Vegas.

The scan below shows some more that were used in other states and on cruise ships. A very interesting part of the color token collecting specialty.

By the way, there was a conventional $1 Chipco chip made that had a design identical to the choken you showed. Similar designs were used on 5 and 25 chips as well during the anniversary celebration.