pamphlet Hako letter scale
This letter opener has a built-in letter scale. With this scale one determines whether the weight of the letter is below or above 20 grams. This combination is a design made by Hans Kosack from Berlin, Germany. It was protected with a simple German patent, a Gebrauchsmuster, with number DE1877236U at August 8 1963. The application date is February 6 1963. The specimen at the photos lost the original transparent covers. The red limit lines at the replacing covers were made by me with a marker. The original letter opener and scale was sold in a box with leaflet and had the mark Hako. A gold and a silver colored version exists. Below some more pictures of this letter opener with the built-in letter scale.
detail of the scale
