Estonia #NB1-6 mint never hinged, 1941 semi-postal set issued under German occupation.   Scott Catalog value $ 10.00, plus #NB1 & NB2 imperf as a free bonus. 

Nice set with a bit of spotty gum on #NB2.

Buy now at $ 3.50 or make offer.   Postage discounted for purchase of multiple lots.