Vintage Gebr.Gräfrath Fahrtenmesser (Scout knife) from the 1930's or begin '40's.
The handle is made from Trolon, an early plastic that was also used on many Third Reich dress daggers, and which has the tendency to slowly get darker over the years.
Gebr. Gräfrath manufactured knives in Widdert (part of the city of Solingen) from 1878 until 1961, when the company was bought by Hubertus, another Solingen manufacturer owned & operated by the Kuno Ritter family to this day.
Specs:
Overall length: 22,4 cm
Blade length: 13,0 cm
Maximum blade thickness (ricasso): 4,6 mm
Steel: hot drop-forged carbon steel
Handle material: brass guard, brass & fiber washers, one-piece Trolon plastic midsection, aluminium pommel with brass screw.
Sheath: Leather