Standard Noise Level Ear Microphone, Beige. Ear Microphone System (EMS). Ear Microphone for standard noise levels (up to 95 db). Factory Mutual Approved, this compact unit picks up the voice through bone vibrations in the ear canal. The miniature earpiece leaves the hands free and face unobscured when worn by rescue and hazard protection personnel, who still retain the ability for direct hearing and speaking. For personnel required to wear breathing apparatus, communications with protective masks are as clear as communications without. And its high speech clarity under noisy environments makes it ideal for high noise environments. Available in PTT or Voice Activated (VOX). Interface Module needs to be ordered separately for EMS to work. The HT750 and HT1250 Interrface Modules are: PTT is AARMN4044