The Slash Harken (スラッシュハーケン Surasshuhāken) are wire guided projectiles that are usually attached in pairs on the shoulder joints of a Knightmare Frame.
The slash harken's tip is usually a blunt object which can vary in shape at the end, in the case of the Guren Mk-II, it uses a two pronged claw as its slash harken tip. They can be used in multiple ways varying from offensive to defensive, or as a means of transportation via anchoring them in an object, and retracting the cable, or in the case of the Lancelot's wrist mounted slash harken the cable can be stiffened and then used like a pole to vault in a direction (In the second episode, Suzaku even used the wire of slash harkens as a whip). Some Knightmare models change the placement of the Slash Harken to the wrists such as the Tristan, Shen Hu, and the Lancelot which locates pairs both on the wrists and hips. Other variations include the placement of a single Slash Harken in the chest of the Gekka, Akatsuki, Zangetsu, original Guren, while the Gawain and Galahad use ten Slash Harken in place of fingertips. Several slash harkens are also mounted with unique equipments such as the Tristan's which are capable of combining and releasing an energy blast, the Shen Hu's which can send an electrical surge capable of destroying other knightmare frames and rotating along with the wrist and in the case of the Guren S.E.I.T.E.N. Eight Elements the right arm that equips the Radiation Wave unit is also equipped to function like a slash harken. Another unique equipment for some slash harkens are Harkens Boosters, which increases the speed of the harken and can also change its tracjectory for better versatility. A slash harken was also fitted to the butt of the Brake Sword used by Kyoshiro Tohdoh's custom knightmare frames: the Gekka and the Zangetsu.