He wears the standard high collared, full body uniform of the Konoha medical ninja.
As a medical-nin Mitate has basic knowledge of medical treatments and ninjutsu, as well as good chakra control in general. His experience allows him to immediately recognize a fatal injury.
Chūnin Exam Arc
He examined Rock Lee's body after his battle with Gaara. After reaching the conclusion that Lee's injuries are too severe to completely heal, he told Might Guy that Lee will never be able to be a ninja again.