Progressive Knife

A Progressive Knife (often called "Prog Knife" for short) is a combat knife stored in the left shoulder pylon of an Evangelion which uses it, and is one of the Evas' basic armaments. The blade of the knife vibrates at an extremely high frequency, increasing its cutting sharpness to the point that it can cleave the matter of a target object at a molecular level.

Eva-01's Prog Knife is shaped like a simple Bowie Knife.

Eva-02's Prog Knife is a more advanced version, which is shaped similarly to a utility knife: if the current blade is damaged or snapped off, a new one will extend from the handle to take its place.

Eva-00, as built, had no pylons and probably had no Knife. However, it was issued with one during its reconstruction, and its Knife was seen once, very briefly in Episode 12; Eva-00's prog knife looked exactly like Eva-01's. No other Evas besides Eva-00, Eva-01, and Eva-02 are ever seen using Progressive Knives.

Notes

• The concept of a bladed weapon being vibrated at ultrasonic frequencies to increase its sharpness is actually fairly common in multiple science fiction genres; in particular such "vibroblades" are frequently utilized in the Star Wars universe.