Folding knives with a backlock (or spine lock) mechanism. Within the handle, the top of the spine and the tang of the blade resembles a hook. When the blade is opened, it pushes the spine out until the notch on the spine and blade are hooked into place. The two notches exert pressure on one another to keep the blade opened securely. Replacing the blade into the handle of a backlock knife requires pressing on the bottom of the spine until the two notches clear one another.