Thanks Trainwreck,

I wasn't able to find anything on the web.
I just kept finding receips for french Lemon tarts.

So if I am right, it's a company that wanted to compete against american express, and forwarding letters was part of his business. Guess didn't work well, since I never heard about it.
And yes littleriverphil, I believe that the number in the middle may be the number of letters forwarded.
PS:Wonder why this subject was removed from US postal history forum, and placed in the World covers,

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