Japanese Pocket Knife.

The Higonokami so popular in Japan has been manufactured almost exactly like this for more than a century. The handle is made from folded sheet brass; the 3 mm thick (not lockable) blade is made of three layers, a Japanese specialty: A core of hard carbon steel that makes for remarkable edge-holding ability sandwiched between two layers of softer steel. If closed, the blade completely disappears into the handle. The Higonokami is opened with a lever at the joint.