|Use||Recording dying Andalite messages. Restoring a nothlit's ability to morph.|
|Behind the scenes|
|First appearance||My Name is Jake|
|Last appearance||Face Off|
The Andalite disc was a piece of Andalite technology given to the Animorphs in the TV series by Elfangor-Sirinial-Shamtul. This disc, and presumably others like it, operated on DNA encoding - this particular disc was encoded to recognize the DNA of Tobias, so that it would activate only when touched by him. The Yeerks, and Visser Three in particular, were considerably interested in unlocking the secrets of the device, and they attempted to do so many times throughout the series, to no avail.
The secrets of the Andalite disc were revealed when the Animorphs finally recovered it - it carried a message from Elfangor to Tobias, explaining to him the nature of the disc and the choice it offered him. With the disc Tobias was able to restore his ability to morph. The disc also allowed him to acquire his original human DNA as a morph. Whether the disc has any connection to the Ellimist is never revealed.
Whether this disc is the only one of its kind, or if others like it exist, is also never revealed.
The disc was refered to as a Herok Disc in the Series one episode "The Alien".