This vintage map distance meter (Curvimeter) was made for maps with scale 1: 50 000. Item is used, but the scale is clearly readable, the plastic covering the scale is a little yellowish (long time storage). Made in Czechoslovakia in the 50's/60's Otherwise very nicely preserved item in full working order. How to use it?
You simply place it at the starting point (map with scale 1:50 000) and move it until your will reach your final destination. After that you can start to read from the device. Each segment represents 1 km. On the other side of the item, there is a measuring scale in cm. Each segment represents 1 cm and 1 cm on map with scale 1:50 000 = 500m = 0,5 km. Item is very small and light, so you can easily wear it in your pocket.