Energy Efficient Building 50 sen - Ring Flaw

The 50 sen stamp of the Energy Efficient Building set issued on September 9, 2009 has a ring flaw. The ring flaw is in green colour located at the top right corner of the stamp. The flaw is consistently observed in some stampsheets (only one stamp in stampsheet affected). Go and check you stamps if you also posses this ring flaw!


the stamp on the left is normal; the stamp on the right has ring flaw
the ring flaw is on the top right corner of the stamp