WW1 German Fliegertruppen Aircraft Variometer – VERTICAL SPEED INDICATOR – RARE!

This instrument measured the vertical speed climb/decent using the angle of instrument itself (needle moves up and down based on the angle/attitude of the instrument).  It was located on the main instrument panel of many German aircraft.

Made of an aluminum housing, this is instrument is in EXCELLENT functioning condition! Made by Franz Herkenrath, AG., Zürich, it was most likely manufactured between 1915 and 1930. Some marks and wear, due to the age, but nothing that detracts. Not sure of the exact aircraft it was used in, and I have never seen another one like it! Would make a PERFECT addition to any collection or display!