Max Spark (マックススパーク Makkusu Supāku) is both a transformation item, given by Ultraman Max for Kaito Touma, and a bracer for Ultraman Max. With it Kaito can transform himself into Ultraman Max. The Max Spark also serves as a weapon for Max, used for his finisher the Maxium Cannon among other powers.
Transformation: Kaito raises the Max Spark and puts the Max Spark on his left arm to transform into Ultraman Max.
Maxium Cannon (マクシウムカノン Makushiumu Kanon): Max raises the Max Spark on his left hand gathering particles and fires a left-handed "L" style beam. This technique is often misspelled as "Max Cannon".
Purifying Wave: Like many techniques, it is charged by the spark itself. Max used this to quell Natsunomeryu's anger and seal him away.
Maxium Reverse (マクシウムリバース Makushiumu Ribāsu): Max can release a golden light from the Max Spark.
Energy Reflux Tactics: Max can discharge energy from the Max Spark. Used to from himself from Metacisus.
Multiply: Max can multiple in many copies of himself with the Max Spark and doing his own version of the Ultra High Spin.
Max Typhoon (マックスタイフーン Makkusu Taifūn): When using the rectangular barrier, if it is being attacked Max can use the Max Spark to make the shield absorb the beam and transform into a tornado. The winds are strong enough to tear to shreds anything inside it.
Power Endowment: As revealed in episode 8 of Ultraman X TV series, Max/"Kaito Touma" can bestow a portion of his powers into any form of objects in mind. He manifests this in a form of a Type U Cyber Card. This not only gives Ultraman X the means to summon a Max Galaxy, but can also summon the Ultra Warrior in person to when humanity's hopes resonated with his card.
The Max Spark is a combination of elements from the Beta Capsule and the Ultra Eye, just as Max is based on Seven but with elements of Ultraman. It is first held up high, like the Beta Capsule, and then placed on the body to transform, like the Ultra Eyes. It also shares elements of the Armed Nexus worn by Ultraman Nexus and is the inspiration for the Mebius Brace, being that in Ultra Form it is used for several of the Ultra's techniques.
The rise scene is also a mixture of Seven's and Ultraman's, it has Kaito being changed into Max thanks to the light from the Max Spark and then him growing to a giant size.
In the Indonesian dub he shouts "Max" after raising the Max Spark.