Domestic letter with perfin “A.T.Co.” in the stamp. The letter is franked correctly with 15 øre, which was the rate for domestic letters from January 1st 1927 to June 30th 1940. The stamp is cancelled January 21th 1936 with TMS nr. 31. 3 København *OMK*. January 1936 increases the usage period of A.T.Co. with mare than 22 years.