The Escafil device appears in Animorphs as a four-by-four-by-four inch, blue cube, according to Jake's description of it in The Invasion:
It was sky blue and square, maybe four inches on each side. It seemed kind of heavy for being so small.
To give the five children the morphing power, Prince Elfangor instructs them to each press one hand against one side of the cube; he then places his hand on the sixth side, and presumably operates the device, in an unknown manner.
Something like a shock, only pleasurable, seemed to run through me. A tingle that almost made me laugh.
The Escafil device's material composition is unknown, as is its internal structure or the manner in which it bestows the morphing ability upon the user. The device was named after one of the creators of the morphing technology, an Andalite of genius intellect by their own standards. In The Hork-Bajir Chronicles, the Andalite character Aldrea mentions that the mother of a friend was a developer of the technology; the book does not mention if this individual is Escafil. Indeed, it is unclear whether Escafil was a male or a female, though the latter is more likely; the books mention that scientific research is considered an appropriate field for Andalite women, while males tend to be warriors (although by the time of Elfangor, the Andalite military sought more well-rounded warriors, proficient in battle as well as the arts and science). Ax mentions that the Escafil device is known by other names, but none are ever given.
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