Yealink YHS36-M Mono Ip Phone Wideband Ear Rj9 Headset, Wired Headset, Black and silver, Wideband Microphone, Microphone Sensitivity-44.0 dB re. 1 V/Pa, Speaker sensitivity 93 dB SPL 1 kHz, 60 mV, Input Power normal 5 mW, max 10 mW, Speaker bandwidth Wideband. Yealink YHS36 is the over-the-head style headset which is made for office worker, SOHO, or call center staff. It supports QD (Quick Disconnect) feature and it is compliant with the full range of Yealink enterprise IP phones.