A sterile implantable magnetized device intended to be used to magnetically hold in place a head-worn bone-conduction hearing aid (against the skin on the side of the head), usually using a base plate. It is metallic, typically flat-disc- or dual-disc-shaped, and permanently implanted with screws in the mastoid process or parietal bone of the skull. Disposable devices associated with implantation may be included.
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