Unless I am confused, There are a couple of options with the Airtights for Chips. First you can get the 39mm which is Direct Fit. I am not positive, I will defer to your experience over mine, but I thought the larger 40mm chips will not fit in those. Then there are AirTites that are larger (Oversized for chips), Can't remember the size but they have a foam ring inside that is the outside diameter of the size of the AirTite and inside diameter of 39mm. Of course you can fit get these rings to fit the outside diameter of various sizes of holders then you order them to fit the inside diameter to what you are putting in. The second option are the holders that I prefer. They all fit in the same diecut cards and the size variations are made up in the foam rings. This is what, I think, you are referring to that the 40mm will fit in the 39mm rings. It is a tight fit but the foam does comnpress a little and will allow it to work. This is the very reason that I prefer the larger holders with rings. It saves me the trouble of having to have too many holders on hand.

As it is right now, I have Whitman(?) Square holders that hold all my tokens. Since the boats here in Illinois all use tokens that means 2 or 3 different sizes of those to hold the .25, .05 and .10 tokens. I think the .05 and the .10 go into the same holder but I have to have a different size ring. My Quarter tokens might be direct fit in those holders, I can't remember.

Then there are the AirTites that I use for Chips and another size AirTite that I put all my Silver Strikes into. I prefer the AirTites over the original capsules that SSs come in as they keep the strikes brighter longer. The factory holders have a little slot in the side, for opening I guess, that actually is a hole that allows air to penetrate. I find that SSs that are kept in the original holders darken fairly quickly.

Add to this the different size diecut cards for the Chip holders, Strike Holders and if I were to go with direct fit 39mm holders that would be another size cards.

Maybe I am a little picky but I try to keep things down to the fewest things that I need to keep on hand and most simplicity.

Incidentally, I won an auction on eBay recently for a Wholesale Lot (5) of 6" Calipers. I should be getting those soon and it will help me keep the various sizes for all these things organized. Hopefully they will be better quality than the dozen cheap Chineese Boomerangs that I got recently. They were all grosely warped out of shape.