The eagle eye pocket knife is a smaller-sized lockback with a thumb-hole open, instead of a thumbnail pull, for easier use and operation. The knife features a prominent locking mechanism adjacent to the back-end bolster (the lockback “button”) and a single blade. That primary locking blade is a modified long clip point.
There are very famous models of lockbacks, the Buck 110 (see the “Folding Hunter” description page), the Case Mako, etc. The lockback really made its “claim to fame” when Buck introduced the original folding hunter in 1964, marketing it as a pocket knife that was as strong as a fixed blade.