This is a vintage balance scale. The device was made in Kyiv, Ukraine, in 1967. It was a school laboratory scale most likely meant to be used for chemistry lessons. The measuring tool was designed for weights from 0,35 oz. (10 g) to 7,05 oz. (200 g). There is a marking 'КФЗ' which stands for Kyiv Findings Factory ('Киевский Фурнитурный Завод'). All this information is on the arms of the balance (photos 9, 10).
The weighing pans are made of black bakelite. Their diameter is 3,9'' (10 cm). 'Made in USSR' is written on the bottom of each (photo 6).
Length of the beam is 7,7'' (19,5 cm). It is made of stainlss steel.
The pan balance is in very good condition. There is some rust on wire loops for suspending pans. Also one of the hooks is missing. It was replaced with another one accurately made of copper wire. It was taken in account that the size and weight of the new hook have to be preciously measured so that not to tilt the balance.
The balance scale was the first and the simplest mass measuring instrument. It was widely used as far back as about 2000 B.C. And until 17th century A.D. all the weighing scales only were variations on the balance scale.