Bulma designs both the watch and the costume within only two hours of Gohan's request. He wants it to help fight crime in Satan City while still keeping his identity a secret. Videl later acquires her own watch to turn into Saiyawoman (or Saiyaman II) to fight alongside Gohan.
Video Game Appearances
In Dragon Ball Xenoverse, the Great Saiyaman Watch is worn over the top of the left hand gloves worn by Great Saiyaman and Great Saiyaman 2. It also appears on the Future Warrior when they wear the Great Saiyaman Suit's hand option (males where the one worn by Gohan while females where the one worn by Videl). Its appearance in the game is purely cosmetic.
In Dragon Ball Xenoverse 2, the Great Saiyaman Watch appears on the hand options for the Great Saiyaman Suit, Great Saiyaman, and Great Saiyaman 2 like in Xenoverse. Additionally the Great Saiyaman Watch also appears as part of the hand options for the Hero Suits (Turtle, Crane, Demon, Ginyu Force, Red Ribbon Army, and CC) which are color customizable versions of the Great Saiyaman Suit with different kanji symbols and logos. The Great Saiyaman Watch worn as part of the Hero Suits are also color customizable. Like the watches appearance in Xenoverse they are purely cosmetic.
- The watch is a reference to devices commonly used by Japanese superheroes to perform their -transformations (like the transformation devices in Kamen Rider and Super Sentai)
- The Great Saiyaman Watch is also similar to the ring where DC Comic superhero the Flash hides his costume.
- It is also like the watch Ultra Spider-Man uses to instantly change his costume.