When mounting an electret condenser microphone, the microphone should be mechanically isolated from the product enclosure, so sound and vibration are not transferred from the enclosure to the microphone and to ensure the microphone only receives sounds from the front holes of the enclosure. The thickness of the enclosure in front of the microphone should be less than 1mm, while the holes in front of the microphone should have a diameter greater than 1.3mm for a single hole or greater than 0.8mm for multiple holes. Elongated holes should have a width greater than 0.8mm.