Hey T4, not sure if it's the same design, but Colt has come out with a reproduction named CSAR (Colt Search And Rescue); I've heard it's a good updated reproduction of the original German Paratrooper Knife.
the Colt GPT is made by Eickhorn/Solingen/Germany. This one has a Colt logo on the blade, a serrated edge and a bottle opener as a guard.
It's a civilian version of the original "Kappmesser", the German paratrooper knife with a blade length of 8.5 cm due to German gravity/switchblade knife laws (getting worse
As FullerH wrote the original from WW2 has wooden scales. At that time the German Paras were part of the Luftwaffe (Air Force), not part of the Army and this knife was standard issue for flying personnel because of the room restrictions on planes.
The knife they issue to the Bundeswehr Fallschirmjaeger is the same, only the handle is plastic. The blade length of the military version is 10 cm.
Playing with this knife is fun and you get a nice "Click" when opening the knife but it's by no means a good knife for everyday use.
The blade is wobbly, the lock not secure. You can disassemble the knife in about 2 secs for cleaning, but this and the "cool"-factor are the only positive things about the GPK.
At my time with the "Fallies" I left the Kappmesser at the barracks and carried my own knifes.
The other good thing about the Kappmesser is
that if You break it, You get a new one for
free. There are only a few minor catches to
this deal : They wake You up a 0500, You have
to endure horrible food and leap out of aircraft
These days I LEAP with a wide grin, and I even pay for it. Must be some aftereffect of the food they gave us. Obligatory knife content. The Kappmesser and the Colt also have a spike for loosening tight knots.