Phonak Receiver 4.0 is compatible with the new Phonak Marvel hearing aids, and the receivers are available in three different types: S is the standard receiver for mild to moderate hearing loss, where M is for stronger hearing loss and P is for the strongest hearing reductions.ALL TYPES ARE AVAILABLE!!! It is also easy to tell the difference between the hearing aids as the end of the receiver is red for the right ear and blue for the left ear.
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