Flutter mucus clearance valve

Has anyone tried one and what are they like to use? I have been taught physio but sometimes I find the gunk so hard to shift

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hi.I have one.mine is white and looks a bit like a pipe end.It has a metal ball inside and when you blow it vibrates and you can feel vibration inside and losens mucus.I also take carbocistine that is my best friend now couldnt cope without it as lungs were constantly full of mucus.Love Glynis x

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I got peri pep aid similar idea. Basically as u breath in the ball vibrates this vibration is passed into the lungs which breaks up the secretions. makimg it easier to disperse when u cough at end of excercise. Its A lot better than the peri pep