SOTR MicrophoneA noise canceling, dynamic, respiratory mask microphone designed for the Ops Core SOTR (Mic model only). The mic is designed for use with a headset that has a 2 prong U 173 input plug. NOTE: This will only work with the SOTR Mic model, the standard SOTR and SOTR Lite are not compatible with this product. Optimal design, seamlessly integrates into the respiratory mask for maximum performance. MIL STD 810G, w Change 1 Environmental MIL STD 461G Control