Phonak CeruShield Wax Guards. CeruShield wax guards have been designed specifically to be used with the SDS4 receivers used on newer Phonak RIC hearing aids, Audeo M, P and L (Marvel, Paradise and Lumity), also Unitron Discover, Discover Next and Blu RIC hearing aids, and also Specsavers Advance x39, x70 and x71 (x representing the technology level ie a 3 digit number ending in 39, 70 or 71).
