In the comics, the Phantom is a masked crimefighter who protected the innocent from pirates, hijackers and other evildoers. While not as dashing or exciting as its costumed namesake, this electromagnetic phantom -- a carbon and polymer mixture that simulates the human body -- is being readied by the National Institute of Standards and Technology for its upcoming role as a different kind of protector. The NIST phantom serves as a mannequin in a standardized performance test for walk-through metal detectors or WTMDs such as those used at airports.