The reason the seal broke was because of Eiji's lack of desire, which made him perfect to become OOO. However, someone else can perform the physical action of scanning Medals for Eiji as long as he is wearing the OOO Driver. According to Ankh, because it was Eiji who undid the seal on the OOO Driver itself, it will only work on him and no one else. To transform into OOO, Eiji inserts three Core Medals into the O Slater ( オースレイター, Ō Sureitā), turns the O Slater on the Force Drive ( フォースドライブ, Fōsu Doraibu), scans the Core Medals with the O Scanner, and then holds the O Scanner up to his chest. The Transformation Belt OOO Driver ( 変身ベルト オーズドライバー, Henshin Beruto Ōzu Doraibā) is a belt that gives Eiji Hino the ability to become Kamen Rider OOO, originally the seal that kept the Greeed in their 800-year slumber.
