All About Pocket Knives

Does anyone own one of these? Or perhaps have some experience in a knife shop with this or a similar model? I have seen some pictures on Google that shows a lever in the scale for knives produced prior to World War 2. With this text on Hartkopf, it suggests the cap lifter replaced the 'lever'. Can anyone confirm this?

Thanks,
Sid

Hartkopf Stag Pocket Knife 345410

With the spring lever handle model, Hartkopf revives an old tradition from the 1930s. To adapt it to the present day, the spring knife has been replaced by a cap lifter, which releases the blade’s locking mechanism in the open state by pressing. The blade is hand-forged from traditional 1.4034 stainless steel. The elaborately manufactured springs are made of C45 spring steel. Solid nickel silver jaws and brass plates in combination with a horn of deer antler give the knife its unmistakable character.