This item is in Good Used Condition.  A very rare knife was acquired by the owner in the mid to late 1960s.  This knife goes by a couple of names, i.e. Verlängerunsamesser ( Extension Knife ) and Saustecher (Pig Sticker ). It is a sheath knife with a short blade for normal use or it unfolds/extends to a longer blade. The use of the longer blade is used to make a final kill by inserting the blade into the vitals of the animal, usually, a pig. These knives were typically used in conjunction with a Saufeder ( Boar Spear ) After spearing the animal, a final dispatch may be necessary.
As to this knife, it has seen some use. There are sharpening marks on the blade but the Puma Logo remains bright and clear.  The lever lock mechanism intermittently works. It locks in the open and closed position if you depress the lock., otherwise, it does not.  Also, the sheath lacks the typical belt loop. It appears to have been removed.
A very, very rare knife that you typically do not see outside of Germany. It is also a very rare item there. I would think parts for this knife are non-existent but I still believe it could be repaired and restored by a professional with the necessary skills if the new owner wants to do that.
Overall the knife is 12 inches.  The folded blade is 4 inches and extended/folded out it is 8 inches.