The Decadriver is a belt that gives Tsukasa Kadoya the ability to become Kamen Rider Decade, based around the Rider Cards. By inserting a card into the Decadriver, Decade can invoke the cards' abilities. In Complete Form, the Decadriver is moved to the right side of his belt where Decade inserts his Final Attack Ride Cards and activates them by touching the Decadriver's window.
As seen in Kamen Rider × Super Sentai: Super Hero Taisen, along with Blade's Blay Rouzer and Ryuki's Drag Visor, the Decadriver is also compatible with at least some of the Gosei CardsIcon-crosswiki used by the Tensou Sentai GoseigerIcon-crosswiki. This is shown when he is given the Reflecloud card by Gosei RedIcon-crosswiki to counter Kani Lazer's beam attack.
When Kamen Rider Decade transforms into the previous Nine Heisei Riders using the Kamen Ride Cards, he still appears sporting the Decadriver in the place of their respective belts, to use his various Attack Ride cards. However when he disguised himself as Kamen Rider Ichigo, the Decadriver took on the appearance of Rider 1's Typhoon belt, unlike other Kamen Rides where the Decadriver is still present. It changed back when the Decadriver/Typhoon was struck by Captain Marvelous as Akarenger. It is unknown if this is a property of the card itself or a yet-undemonstrated ability of Decade's.
In the film, Decade is transformed by a Decade Final Form Ride Card into the Jumbo Decadriver, a larger version of the Decadriver which is worn by a Kamen Ride Card-summoned Kamen Rider J to transform into Decade Complete Form Jumbo Formation. This form is identical to the usual Complete Form, apart from the fact that Decade is now many times larger, and wears the Decadriver on the front of his belt, with no K-Touch.
- Change announcement: KAMEN RIDE
- Form Change announcement: FORM RIDE
- Attack announcement: ATTACK RIDE
- Rider Form change announcement: FINAL FORM RIDE
- Final attack announcement: FINAL ATTACK RIDE
- Decade Complete announcement: FINAL KAMEN RIDE