scope:

This specification covers headsets and headset-microphone assemblies intended for use in medium ambient noise level environments of 85-105 dBA SPL (Sound Pressure Level). These headset-microphone assemblies shall use dynamic earphones of the moving coil type that transform electrical energy into acoustical energy and shall be a complete assembly including headband, earphone(s) mounted in rigid earcups, with cord assemblies to meet requirements of various military service activities. The assemblies shall include, as required, a noise cancelling microphone and boom.