POSSO
letter scale

The Posso is a popular letter scale. It is a brand name from France. Who produced these letter scales, and where, is unknown to me. In documentation of the Testut company from the years 1965 and later 1977-1978 older models of the Posso letter scales are shown. The model shown here probably dates from the 1980s and later. At least three weighing ranges were made of this model: 100, 250, and 350 grams. With scale divisions per gram, per five grams and per ten grams. The scale base, frame and scale mechanism are made of black painted magnetic steel. The scale, the zero adjustment screw and the rivets are made of aluminum. The letter plate is made of transparent plastic. The counterweight and the insert ring of the letter plate are covered with red plastic. There are still some minor differences between these three versions. The letter plates of the 100 gram and 350 gram versions have a raised edge of 3 millimeters high. The letter plate of the 250 gram Posso is completely flat, without a raised edge. The weight of the letter plate is 25g, 66g, and 91g respectively, the differences can be traced back to different dimensions of the insert rings. The external dimensions of the letter plates are the same 11 x 9 centimeters. The scale height and the dimensions of the scale base are also the same. The 100 gram Posso has already been shown, see here. The 350 gram version does not have its own page.
Some specimens have the following French text on the base of the scale:
MADE IN FRANCE --- [Made in France]
NON VÉRIFIÉ PAR L'ÉTAT --- [Not verified by the state]
INTERDIT A L'USAGE COMMERCIAL --- [prohibited for use in commercial trade]
The scale height is 16.0 centimeters, the scale base is 16.5 x 9.5 cm.
Below are some more images of the Posso letter scales.