"Slabbing" is the term for a "service" provided by a company that grades a chip and then places it in a plastic holder where it can't be removed or handled. The container usually has a card telling what the chip is and what it's "grade" is. The chip can't be removed without destroying the container. The same thing is done to coins and sports cards. There are lots of reasons to oppose slabbing. Most of us feel like it's an unnecessary and the "gradings" are highly subjective. To me, it makes chip collecting all about the value of the chip and not about the chip itself or the history of the casino. Slabbing has ruined coin and sports card collecting for a lot of people and we don't want to see it happen to chips. You can learn more by visiting:
http://www.slabfree.com