Acoustic amplifiers (hearing aids) for partially deaf persons; Ear adaptors for hearing aids; Earmoulds being parts of hearing aids; Hearing aids; Programmable hearing aids; Listening apparatus for use by persons with impaired hearing; Medical hearing instruments; Medical instruments for use as aids to hearing; Medical instruments for use in relation to hearing; Apparatus for use in alleviating hearing disorders; Apparatus for use in testing hearing disorders; Apparatus for use in treating hearing disorders