Israfel is a vaguely humanoid Angel with the capacity to split into two "twins", which are morphologically nearly identical to the single-body form apart from size and coloration: the twin designated Alpha is gold, and Beta is silver. The twins are roughly the same size as an Evangelion, while the single body is noticeably larger. Even when completely independent of each other, both twins act in synchronization.
The face on Israfel's single-body form is shaped like a blue and red Yin-Yang symbol, with two eyes that are capable of blinking. Both twins have a gray plate with three eyes in a triangular configuration, which are capable of firing energy blasts. The single-body form has only one core, while each of the twins has its own core. Both the bodies can rejoin spontaneously, although the two cores take longer to fuse.
When Asuka cleaves Israfel completely in half it does not bleed at all, or appear to possess internal organs of any kind other than the core. Its insides are composed of a uniform pink fleshy material.