Imparters are an Elvin invention using technology that allows the user to call other elves' imparters as a method of communication, without any actual physical contact. The word Imparter means "an object that tells or relays information."
It is a square silver gadget.
“Imparters were the elves' much sleeker voice-commanded version of a videophone.”
Imparters are thin silver metal squares that operate through voice control. For example, if an elf were to hail Elwin, they would say, "Show me Elwin". Once the hailed elf has connected, the device works like a video phone (unless someone tampered with the wiring to make it only output audio, as Lady Gisela does in Book 6: Nightfall). When contacting a Councillor, one needs to have been given clearance first by the Councillor themselves.
An Imparter can also display text across its screen, and can send messages similar to human text messages. When an imparter flashes "out of range" when trying to contact someone, it means that the contact is in one of the few places where imparters don't have signal (often dark, forbidden locations).