Zero Gear

Zero Gear (5) (ゼロギア⑤) is a gear that when equipped turns that corresponding person's weapon into their signature weapon; in Roxas' case, he will wield the Kingdom Key+. It's 4 spaces wide, with a square directly below the Gear. It also has room for 4 support pieces.

Trivia

 * If this Gear is equipped with one Ability Unit, the Keyblade will turn into Oathkeeper. If it's equipped with two, it'll turn into Two Across. If it's equipped with three, you'll turn into Dual-Wielding Roxas with both Oathkeeper and Oblivion which is only accessible during Mission Mode.
 * This gear has the Nobody insignia to signify that each of the weapons this gear equips is a signature weapon of the Organization XIII, except Roxas.