Notes

https://en.wikipedia.org/wiki/Bone_conduction
https://en.wikipedia.org/wiki/Bone_conduction_auditory_brainstem_response

http://cyberpunk.asia/cp_project.php?txt=233

GD01

imensions: 21.5*14*7.9mm Power Nominal input 1.5W, Maximum input 3W Average voltage :3.7 V Operate (Max) :12 V Nominal Impedance :4.5Ω±15% test @200Hz 3 v Resonance frequency :300-19000HZ Sound pressure level (minutes) :In the case of 88-1kHz decibels Current consumption (maximum): 600MA Distortion :5% less Operating temperature :-20—60° C Storage temperature: -30—+70 ° C