A system and method of controlling a bi-directional switching operation for a synchronous transfer mode signal transmission line of an asynchronous transfer mode switch is disclosed. The central control computer can transmit, among other things, operational software and threat profiles to the threat scanning machines, while the threat scanning machines can transmit, among other things, images and performance data to the central computer. One or both of the jaw members includes a jaw frame and a replaceable component engageable with the jaw frame.