Classify 2 Envelopes

I´m from Argentina. Can´t properly classify these 2 envelopes:



Thank you.

Hi mac123 and welcome! Your envelopes are called window envelopes. They were franked using a postage meter which enabled a business to print a label for postage (instead of having to buy stamps) normally for a reduced rate. Both envelopes were handstamped "foreign" and "via air mail" probably by the sender. And the bottom cover has a great slogan cancel on the postage label saying "philately the family hobby" - very nice!

mac123: Jenny2U is correct in that these are window envelopes franked with meter postage. Just as a minor clarification (sometimes I read too much into things) these are not Postal issued stationary items. These are probably pre-printed, common business stationary with the return address printed by private printer. (I worked for the F. S. Webster Company in the early 60s and they made typewriter ribbons, carbon paper, forms etc. and also provided for the printing of letterhead stock and envelopes. The business was sold to a larger firm Inter-Chemical (I think) in 1967 or 69.) The meter strip might have some history and should be discerned from the imprint. The envelopes themselves were probably dropped into a street collection box (rather than being dropped off at the local Post Office) as they show cancels. Curious.. are the meter dates & the cancellation date the same?? Also like the bottom cancel...

Thank you very much.