Interface Headset

An Interface Headset is a small device worn on an Evangelion pilot's head, which interfaces with the "A10 nerve" of the brain, allowing a pilot to synchronize with an Eva and control its movements. Interface Headsets appear to be two small plastic devices placed on top of the head, one on either side. However, the entire headset is actually one object: they are connected by a thin wire tiara of sorts which connects to two larger pieces atop the head. The wire tiara section is always obscured from view because it is nestled under the pilot's hair, making it appear as if the two larger pieces are simply stuck on top of their head.

Notes

• Exactly what Interface Headsets are and how they function is never explicitly elaborated upon on-screen, but is from Gainax-released background material, such as the Red Cross Book.
• Eva pilots are never seen putting on or taking off Interface Headsets during the entire series. The wire tiara which actually connects the two larger pieces and supports them in place on top of the head is also never seen on-screen, but only in behind-the-scenes production sketches. This has resulted in many fans assuming that the two plastic pieces clearly visible atop the head are somehow just "stuck" on the head, either with adhesive, by being attached like a hairclip, etc. when actually the entire thing is a single headset. As these objects were never formally named on-screen, fans frequently refer to them as "A10 nerve clips", because the description of them in the Red Cross Book says that they interact with the A10 nerve. However, script production notes (released with the Renewal of Evangelion DVDs) clearly and repeatedly refer to the object as an "Interface Headset".