Sistema C.A.I. or Cambio Arma Istantaneo (Instantaneous Armament Change System) A complex puzzle of four Storm Boxes, four Rain Boxes, two Lightning Boxes, two Sun Boxes, and four Cloud Boxes. Only one who can utilize all five of these types of Dying Will Flames can use this Weapon to full effect. So far the only person capable of it is Gokudera. The main structure is a set of four circular bone Shields that protect the user from Attacks or can immobilize enemy's Box Weapons. The Storm Flames of the bone Rings are lightly covered in Rain Flames, which neutralize the initial part of the Attack. Of the sixteen Boxes, there are four Skull Rings for each of the other Dying Will Flames, Uri , and Flame Arrow. The main method of Attack of burst of Dying Will Flame or missile projectiles that have two kinds of Flames. The strength of this combination is the instantaneous change from one Weapon to another, which give the Weapon a high degree of unpredictability. The most powerful Attack is the combination of Storm and Lightning Flames into a concentrated burst called Flame Thunder. Gamma believes this to be an Original invention of Innocenti, because of its flashiness.
- Uri A Leopard Cub with very little physical power and often fails to listen to its owner. When treated with the Sun Flames' activation properties, Uri grows into a gigantic leopard with Flaming wheels on its shoulders. Its physical strength is dramatically increased, to the point that it can fight on par with Gamma's Nero Volpi. Its true name could be Leopardo Tempesta (Storm Leopard).
- Flame Arrow A Cannon strapped to the users left arm with a Skull's face and a barrel aimed out of the Skull's mouth. Another Skull is on the rear end of the Cannon, where ammo is inserted, which can be real bullets or even Dynamite. The Cannon's main attack is a burst of pure Storm Flames, but can also utilize special missiles when mixed with other types of Flames. It's most powerful Attack is Flame Thunder, which is a mix of Storm and Lightning Flames in a strong burst. The Cannon can issue instruction in Italian by spelling words in Dying Will Flames. If no bullets or ammo is loaded, the cannon releases a burst of air that extinguishes Dying Will Flames.
- Rain: By coating the storm rockets with the Rain's Tranquility, enemy's Flames are weakened, allowing the rockets to penetrate the enemy's Defense.
- Sun: The Sun's "activation" and high power output increases the speed of the Storm rockets, creating an Attack with unpredictable acceleration.
- Cloud: The cannon fires one shot that spreads in a tree-diagram like fashion, due to Cloud's propagation, creating a wide spread attack that is difficult to avoid.
- Lightning: Creates an attack known as Flame Thunder , a solid beam due to the Lightning's solidification characteristic. Gokudera claims it is his strongest Attack.
- Contact Lenses: These Contact Lenses also came with Sistema C.A.I. and allow Gokudera to aim extremely accurately at an enemy by taking into account things like gravity and magnetic fields when aiming. They are to be based on the same technology as the Contact Lenses that Tsuna used to complete his X-Burner.
- Shields: These Shields are also part of the Sistema C.A.I. and were to be enlarged once they have Contact with Dying Will Flames. Gokudera used them to block the attacks of Gamma when they fought after Gamma defeated Ryohei inside the Melone Base in the Future Arc.
- Storm Disc: This Storm Disc is also part of the Sistema C.A.I. and by riding a top of it Gokudera can move at high speed like Tsuna with his X-Gloves, but cannot fly. Its first used in the battle against Gamma.
- Gokudera's Skull Rings: The Skull Rings were hidden within the parts of the Boxes. The Rings that belong to the Sistema C.A.I. and are of the Lightning, Rain, Sun, and Cloud Attributes.