Ralph - the jars called Atlas Mason" were originally sold with spaghetti sauce in them, not as canning jars. For a number of years the regular lids fit them fine and many of us used and still use them today. But at some point the sauce producer decided to change the jar size/threads so the lids wouldn't fit. Rumor has it they didn't want a law suit if the jars were used for canning.

I can't recall offhand the year the change was made but if regular lids won't fit them they are probably the newer model jars.

One possible source of 1 piece lids that "might" fit is fillmorecontainer.com. They carry some unusual sizes.

There are a couple of previous discussions here about them that might be of interest to you. The search will pull them up with "Atlas jars".

Dave

Link to one of the previous discussions:

http://forums.gardenweb.com/discussions/1955055/canning-jar-lids