The answer you're looking for is

Close Cover Before Striking,

which advice was prolly statutorily required here in the US on all matchbook covers. I assume it's still printed there, but I cannot remember the last time I saw a book of matches.

But I've always wondered if the more correct answer were not:

United States of America

in a tie with:

In God We Trust

found on every coin and bill the US issued during the same period. Certainly the latter two phrases are still around literally billions of times, since coins don't wear out as much as matches do.

And I'm way too lazy to go looking for matchbook production figures! Not gonna do it, it's my birthday and I don't have to do anything. Nyaa nyaa nyaa!

TEd, feeling a bit whimsical this AM


TEd