Rapid changes in temperature, such as the phone from the warm car to get the outside of the cold air, or such as the pressure caused by the plane to take off and landing, etc.. The build-up of pressure in the sound chamber or in the chamber will generate bias on the surface of the sensor (e.g., the speaker and / or receiver). This effect will reduce the sound output, or even damage the microphone. LeaDer company can provide ventilation and can prevent water vapor materials installed in the audio equipment, for customers to solve the production bias affect the sound quality due to temperature change. It can prevent the sewage residue attached to the electroacoustic equipment quality influence. the permibility membrane are always used  In the mobile phone speaker, microphone, receiver.