Let's Take it Back to 1975

Here is a small series of stamps created by Israeli designer Eliezer Weishoff in about 1975. It's a great piece of graphical design, with in which if I were buying stamps would love to have these. I wish more graphic designers would do this (come to think of it, maybe I'll try my hand in making them. :)
BTW these stamps also talk about the environmental problems and hazards almost everyone endures everyday. And with a little bit of home, shows a bit of a better solution or care to the problem.

{SOURCE} Courtesy of Richard at Ace Jet 170