Door-Ju

"Open Door! (Steam-like hiss)"

- Unsuccessful shooting announcement

"Charge!"

- Recharging announcement

"Hissatsu: (Shift Car), Full Throttle!"

- Finisher announcement via Drive Driver

The Opening and Closing Loading Door-Ju (開閉装填ドア銃) is a firearm weapon wielded by Kamen Rider Drive, resembling Tridoron's driver-side door. It first appears in episode 8.

Like the Handle-Ken, Shinnosuke names this weapon for the car door attachment on the barrel's side, and Mr. Belt disapproves of his lackluster choice. When the Door-Ju is summoned, it comes from the front portion of Tridoron's hollow section.

Usage
The Door-Ju can fire several shots before needing to be reloaded, which is easily accomplished by opening and closing the door. If the door is open while being fired, the Door-Ju will give an error announcement of "Open Door" (半ドア) and not fire a shot. Once reloaded, it will say "Charge" (チャージ). If the door is opened and closed multiple times while there is still ammo, the bullets will become much stronger. Drive can also project a car door-like energy shield from the Door-Ju by turning the Advanced Ignition on his Drive Driver.

In terms of Drive's forms, Type Technic has the most compatibility with the Door-Ju due to its near pin-perfect precision fitting with the long range combat nature of this weapon.

Finishing attacks
The Door-Ju's Full Throttle finisher PerfecShot (パーフェクショット) is activated when Drive loads a Shift Car into its Shift Landing Panel (シフトランディングパネル) behind the barrel after turning his Drive Driver's Advanced Ignition, with different attacks being performed depending on the car used.
 * Shift Speed: Drive fires several flaming shots, then accelerates them by kicking an energy wheel that forms on the side into their path, slamming into their target at a terminal velocity.
 * Fire Braver: Drive fires a beam of energy resembling the Ladder Expander, which grabs the enemy and pins them to the nearest wall before he pulls the trigger to detonate the energy construct, taking out the target along with it.
 * Rolling Gravity: Drive fires a ball of energy resembling the 10-ton Weight, which flies over directly above the enemy and pelts them with a series of bullets before the energy construct falls like a rock, detonating as it hits the target.

Arms Weapon
The Door-Ju is an Arms Weapon wielded by either an Armored Rider or a New Generation Rider when they transform into Drive Arms. It is absent when Kamen Rider Gaim uses Drive Arms in Kamen Rider × Kamen Rider Drive & Gaim: Movie War Full Throttle, solely wielding the Handle-Ken. However, it is avaliable alongside the Handle-Ken in the Arms Change series.