When forming this metallic arm, he can use it to punch his opponents, or as a makeshift shield to block even a Pacifista’s laser beams. It is unknown if the firearms connected to his metal arm can fire at his will or not. In the anime and Unlimited Cruise game, Kid can also launch compressed bullets of scrap metal at his opponent at high speed.
When using his Devil Fruit ability, purple electrical sparks emit from his hands, so his ability may resemble an electromagnet.
The main weakness of the fruit seems to be its dependence from the surrounding environment, which must contain metal in order for the fruit’s powers to be used (though this weakness has yet to be exploited). Other than that, it is also weak against the standard Devil Fruit weaknesses.