Redizer

The Redizer (レッドアイザー) is one of the two transformation gears for Kamen Rider X, attached to the left side of his Ridol belt, with the Perfecter on the right. For the first 27 episodes (and later in Kamen Rider Taisen), Keisuke Jin used the phrase "Set Up" (セタップ) and jumps into the air with his bodysuit manifesting as he removes the Redizer and Perfecter from the sides of his belt to form his helmet and then snap up the faceplate to complete the transformation.

From 28 onward, Keisuke uses the phrase "Dai Henshin" (大変身) to transform while making a "X" sign with his arms after being powered up by the Mercury Circuit.