The diffuser for the Brevida carries on from the success of diffusers on all masks. They prevent the noise from the exhalation port and also prevents gusts of air from leaving the exhalation port and blowing onto your partner. These are a washable diffuser and can be washed with warm soapy water as many times as needed. the mask can be used without the diffusers but the feedback has been overwhelmingly in favour of these occurring.
