I don't know why I like these official stamps so much, but they just grab me!

These stamps (the verticals, not the two on the lower right, they're older) were issued in three sets between 1955 and 1982.
I've had a bunch of them for a while, and finally decided to add them to my 'just because' collection. Is their simplicity? The impression they look like soldiers standing at attention? I don't know.
Just thought I'd share them.
