Nice one and unusual with a 7 PM Christmas Day date stamp. I'm not sure if your example is just a cut square or the entire cover, but Meter No. 6003 for that date period and denomination of 5-cents Air Mail was assigned to Laboratory Products Company of Cleveland, Ohio and was in use from 09/26/1929 to 01/16/1930.
By the way, Laboratory Products Company was, in its day, a baby formula company started by William E. Telling.
Quote:
...Telling's Laboratory Products Company became the Sealtest Laboratories, and then the S.M.A. Corporation. American Home Products Corporation (now Wyeth) purchased S.M.A in 1938. The innovative Formulac baby food brand name appears to have survived through 1948, but later was used on dog and cat formula. The Formulac brand name is now owned by a small feed manufacturer in Paris, Illinois.
An interesting biographical story of Mr. Telling and his ventures can be found at this link:
http://uncredentialedprofessor.blog...king-of.htmlJust think all of the above information and history was gleaned from just one meter imprint ... and you thought collecting meters was boring!