NEW POWER RECEIVER-SPEAKER by Phonak. Fits RIC (Receiver-In-Canal) hearing aids made by Phonak and Unitron in the last five years including the Audeo, Yes, Naida CRT, and all other Unitron and Phonak RIC hearing aids. These are the newest version of the power receiver; Over time, these receiver/speakers can become impacted with wax and need to be replaced. If you have any doubt, please consult a licensed hearing aid professional as these speakers are not refundable. Thank you for your patronage.