This papercraft is the Eva-02's Progressive Knife, based on the Manga / Anime / Film series Neon Genesis Evangelion, the paper craft is created by rexxkentrix. The Progressive knife is a close combat weapon used by Evangelions to fight Angels.
A knife-type cutting weapon that is stored in an Evangelion's left shoulder pylon and is considered as an Eva's basic armament. The blade of the knife vibrates at an extremely high frequency, allowing it to cut through objects at molecular level.
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.
You can download this Evangelion paper craft here: Neon Genesis Evangelion - Progressive Knife of Eva-02 Free Papercraft Download