|This article is about a/an transformation belt in Kamen Rider Kiva.|
The Transformation Belt Sagarc Belt (変身ベルト サガークベルト Henshin Beruto Sagāku Beruto) is Kamen Rider Saga's transformation device. Transformation is initiated when the top of the Jyacorder's hilt is inserted into the slot on its side, making the blue disc in the middle spin. The finisher is initiated by inserting the Wake Up Fuestle (ウエイクアップフエッスル Ueiku Appu Fuessuru) into Sagarc's mouth for it to blow and inserting the bottom of the extended Jyacorder's hilt into the slot in order to charge it.
It is formed from a miniature individual of the Sagarc (サガーク Sagāku) race, which was created by the Fangire in the distant past. It was used by the first Fangire king, but fell out of use as subsequent kings instead used Kivat-bat the 2nd until he defected from the Fangire along with Maya. The next heir to be born, Taiga Nobori, bonded with the Sagarc as a child and used it to transform into Saga when he became King. Sagarc's whereabouts after Taiga eventually also became Dark Kiva are unknown. Sagarc speaks in the long-forgotten Fangire language, which is now only understood by Fangire royalty, and only speaks modern Japanese phrases during transformation or when a Fuestle is used.
The Sagarc Belt is compsoed of the following parts:
- Demon Emperor Stone (Blue Stone) (魔皇石（蒼石） Ma Ō Ishi (Sõ Ishi)) - A blue stone embedded in the forehead between the Sagarc Eyes. It amplifies the Sagarc Belt's power, and monitors and controls Kamen Rider Saga's power.
- Sagarc Eyes (サガークアイ Sagāku Ai) - The yellow eyes. It is extremely powerful, being capable of identifying ants from a distance of 1000m in the air. It can see through 3m thick lead, and can see in extremely dark environments without light sources.
- Sagarc Jaw (サガークジョー Sagāku Jō) - The mouth, complete with golden fangs. The fangs can emit an ultrasonic wave which is capable of instantly cutting through a 1 m thick steel plate. Its oral cavity is a Fuestle slot, and a Fuestle can be inserted to initiate a finishing attack that is empowered by Kamen Rider Saga's current emotional state.
- Manda Table (マンダテーブル Manda Tēburu) - The central blue circle. It acts as a biological engine and energy stabiliser; rotating at high speeds to generate Magical Energy and stabilise Saga's transformation. It also doubles as a communication organ, and one can communicate with Sagarc by touching the Manda Table.
- Silver Tentacles (シルヴァテンタクル Shiruvua Tentakuru) - The wing-like tentacles on the sides. They are the Sagarc Belt's 'legs', and is a tactile organ that allows Sagarc to feel it's surroundings. There are 8 of these Silver Tentacles (visible from the underside), and each one determines the Sagarc Belt's user, allowing only Saga to transform.
- Jyacorder Slot (ジャコーダースロット Jakōdā Surotto) - A slot in which the Jyacorder is inserted into. When inserted, the Jyacorder will send energy into the Sagarc Belt, allowing transformation and finishers.
- Holding Belt (ホールディングベルト Hōrudingu Beruto) - The strap. It is composed of Doran Mail (ドランメイル Doran Meiru), the same material that makes up Saga's inner suit, and GaoraDoran (ガオーラドラン Gaōradoran) leather, making it extremely durable.
- The Sagarc used by Taiga Nobori to transform is unique as it has yellow eyes.