German WW1 Medics Knife Named Solingen GR Knive

WW1 German Army Medics Folding Knife engraved with the soldiers name and regiment "Haase 8/55" I cannot find another one anywhere. It has a tube compartment for a sewing kit and bandages. It did originally have 4 blades/tools but unfortunately 1 is broken as seen in pictures. One of the blades in marked "GR" with what looks like a crown in-between and "Solingen" underneath, I have tried to photograph this. Very interesting knife.