handheld letter scale

FRANS SVANSTRÖM PATENT is engraved in this handheld letter scale. In 1857 Frans Svanström (1832-1909) started a stationary store and paper trade in Stockholm in Sweden. This letter scale shows the weight up to 19 ORT (1 ORT = 4.2508 grams) and the corresponding rates for sending letter post up to 72 ÖRE (1 ÖRE = 0.01 Swedish Crown). This Swedish postal rate was valid in the period from January 1, 1863 until January 1, 1873. There exists a Svanström letter scale with the same weighing range but with the postal rate indicated in ENKLA. Other Svanström letter scales have more recent postal rates, for example from the period January 1, 1880 until January 1, 1885. Previously, this letter scale of Frans Svanström was shown, with rates from the period January 1, 1885 - January 10, 1907. The magazine Equilibrium has an article A Special Find in Sweden by André Sol & Roland Obst, EQM 2018, No.1, pp. 4460-4463. In it a letter scale of Frans Svanström is described that weighs up to 15 ORT -this was not a postal weight limit, 13 and 16 ORT are limits- and the rate is given in ENKLA as value, this letter scale strangely also comes from the same period 1863-1872.
This scale model is called goose neck. Later came Lindells in Sweden with multiple goose neck models, see for example this Lindells.
Below some more pictures of this old letter scale from Frans Svanström.