what does it mean?
The three-mile drive would have tested Job. Both priests had been awed by legends of the labyrinthine security precautions surrounding the Presidency, and they suspected that their reversed collars would be insufficient identification. Father Thompson raised the subject. "Maybe Monsignor Brady will phone ahead and take care of it," Father Huber said hopefully. "Oh, no, he won't," said Father Thompson. The Monsignor was responsible for Baylor Hospital; Parkland was beyond his jurisdiction. Holding the wheel with one hand, Father Thompson fished out his wallet, extracted his World War II ID card, and laid it on the seat. Father Huber regarded it dubiously. It was dog-eared; it looked counterfeit. That it would impress the Secret Service seemed most improbable. 】
what does "reversed collars"mean?