The German Post issued for the first time a very interesting
philatelic variety on 07.05.2009 commemorating STAMP DAY
by issuing 55+25 C stamps having Safety Perforation in
shape of a Leaf of an Oak Tree between 2 stamps. It sure is
an adoptable marketing strategy, because, instead of buying
1 stamp, the collector has to buy 2 stamps to keep
in tact the shape of Oak Leaf perforation !