J-Decker (ジェイデッカー) is the titular Brave robot of The Brave Police J-Decker television series. He is formed from the Police Combination (警察合体 - Keisatsu Gattai) of Deckerd and the J-Roader. He can then combine with Duke Fire (BP-119 Duke, Fire Roader) to form Fire J-Decker. When combined with BP-601 GunMax and Gun Bike in their Max Cannon configuration, J-Decker is known as J-Decker Max Cannon Mode (ジェイデッカーマックスキャノンモード).
According to Juuzo Saejima, the "J" in J-Decker represents the Japanese police force while "Decker" represents the detective.
J-Decker usually was used as a last resort against monsters too large and powerful for the Brave Police to bring down by themselves, and often in conjunction with Super Build Tiger. He is capable of flying using the wings on his back, which allows him to combat aerial enemies effectively. He can also utilize GunMax and GunBike as the powerful Max Cannon.
A rifle stored in the right leg that has a normal firing mode and can switch to a sniper mode by flipping up a barrel beneath the gun.
- Electromagnetic Baton (電磁警棒)
J-Decker's main close-combat weapon, stored in the left side skirt armor. It is a baton that is electromagnetized to increase damage, retracted into a smaller form when stored. The baton can also discharge a blast of electricity at opponents. Japanese spelling: Denji Keibou.
- Max Cannon
The transformed form of the GunBike with GunMax riding on it, now a powerful cannon which docks with J-Decker's right side skirt armor. This can be considered as J-Decker's ultimate finishing move.
When Deckerd first attempted to combine with the J-Roader, he ran into issues due to having his coding changed when he gained self-awareness. With Yuuta Tomonaga's help, he was able to overcome these issues and combine to beat Barbarossa, a magician using an air force to attack Japan.
J-Decker is flight unit, it mean he won't reduce his movement by special floor effect. Upgrade his J-Buster can earn new attack: J-Buster Gun Mode, 4 range, very useful against enemy only had 3 range attack for counter attack.
J-Decker first appear in episode 2, and appear again in episode 8a(Combine! Build Tiger), however J-Decker joining Chouta at episode 14. Later J-Decker will hide after Deckerd KIA or Might Kaiser arrive, until clear Deckerd is taken (Defeat Satan J-Decker) or Deckerd is Back.
Despite Fire J-Decker will cause J-Decker and Duke Fire (Later Gun Max) got replaced, at Great Mighty Power Dagwon episode, J-Decker and Duke Fire will appear again, because player need J-Decker use Max Cannon for movie collection (need on the fight movie).