Than half a meter
Somehow I was immediately reminded of the characters of some anime with their unnaturally huge swords. This knife Microtech Marfione Custom Halo V 3X OTF Knife has a length of 88 inches and weighs 9 pounds and is an enlarged version of the knife Halo V with vystraivayuschie blade. When the button is pressed the blade is fired with a specific sound, that scares me a little. The blade has a tanto shape and looks very sharp. Handle length — 18 inches, blade length is 13.5. The handle is made of black anodized aluminium.
The mechanism takes the blade with a small motor that works on one battery. And of course, collectible, value is absolutely inadequate, however, as appearance. For this knife you will have to pay 9600 evergreen American roubles.