Gerudo Token

In Ocarina of Time, the Gerudo's Membership Card, or Gerudo Token, allows Link to pass through Gerudo Fortress without being thrown in prison.

Location and Uses
Link obtains this from Nabooru's Second-in-Command after sneaking past all of the Gerudo Guards and freeing the four carpenters, Sabooro, Shiro, Jiro, and Ichiro. Though the Gerudo do not usually grant membership to men, Link's apparent skill earns their respect, and so he is unceremoniously admitted into their exclusive group. This is vital when journeying to the Spirit Temple for the first time, as Link requires the card to have the gate leading to the Desert Colossus opened without being thrown into the jail cell. Additionally, Link is able to walk around freely through the many paths in the Fortress. Link is also able to participate in the horse challenge and training grounds with the Membership Card.