This Briefwaage mit Flüssigkeitsanzeige, this is German, meaning: letter scale with fluid indicator, is a design of Dr. Günter Haag. In 1982 he applied for a patent in West Germany, this was published with the German patent number 3206959-A1 in 1983. Ultimately a patent seems to be granted in July 1986. The letter scale is put on the market by M&M -made in W.Germany- with Art.Nr.687-5 as Universalwaage. The range of the balance shown is 150 grams. The scale is also called water balance and Archimedes scale (or balance). First the outer cylinder must be filled half with water. Then the inner cylinder is placed into the water and the scale is ready for use. It is not the first design of it's kind. For further information, go to "specials".
fluid indicator
