Card-type computer that can capture and enslave Z/X, they produce "Resource" energy of the same quality as that emitted by the Black Point.
The ability to catch Z/X is called "Capture", while the ability to release them is called "Activate". Of course, because the inside of the Device is filled to the brim with Resource energy, it is possible to heal wounded Z/X. While it was developed by modern scientists, it is readily apparent that technology far beyond the limitations of current science has been used in every step of its construction, so there are some rumors that they were built with the cooperation of Z/X with "some intention".
Currently the amount being distributed is quite small, and what few there are has been handed over to government forces, such as police and military, in order to fight the Z/X. But apparently there are tales of counterfeits being sold on the Black Market for huge sums......?
However, even if you are lucky enough to get a genuine model, you still have to win over the Z/X in question, and it said to be a Herculean task to handle. In fact, being able to grab hold of the flow of Resource energy, in particular, seems to require raw, natural talent, rather than any actual age or experience.
The Card Devices are increasingly improved with each passing day, and it is said that there are multiple versions of varying quality in existence.