Using each of the fingers with the thumb used twice, we can open a small lockback knife like this Cold Steel Micro Recon 1 Spear Point . This is a micro functional edc knife with the blade measuring only 2 inches. What separates it from other lockbacks is that is has what is called a 'Triad Lock' which makes sure that the blade will never disengage when deployed and used. Its like you've got a full tang knife in your hands, not worrying that the blade will suddenly or accidentally fold and cut your fingers. A tanto version is also available here . It can be used as a keychain knife, a survival kit knife, or a back-up knife. The pinkie had a little bit of difficulty opening it but its persistence pushed it through. One hand closing is also demonstrated either with the blade pointing up or down. Notice the rubber ring at the bottom of the knife? it is used for Pulling out the knife from the pouch. Extending the grip t...