"Uh..." Tony trailed off, remembering that Borg also came in cubes of power and that he'd just slipped up a bit. Or, well, that he should have explained what he meant before he gave someone like her a heart attack, anyway.
He held his hands up, about 4 inches apart, "Yeah, about this wide and tall. Blue, glowy, kind of like a glass box holding glowing blue light inside. Gives off gamma radiation. We call it the Tesseract."