Older chips, Palms Chips, CIC's and a few others don't fit in the 39mm. Well, sometimes they fit but you have to break them to get the chip out. Here is a great site that I get my airtights from, they sell 39mm, 40.6mm, 42mm, 43mm 46mm, 47mm, 50mm and even 80mm. I think they might also sell a device that helps you determine the specific diameter of round objects.

http://www.air-tites.com/casino_chip_and_military_challenge_coin_holders.htm

Cases are always shipped quickly and very securely. Enjoy!