(1) Clarity Ameriphone HA40 Portable Phone Handset in-line Boost Amplifier It is also known as EHA40 Plantronics HA / EHA P/N 51363.001 PRODUCT DESCRIPTION to severe hearing loss,Increases incoming sounds up to 40 dB louder, and distinction between similar sounding words like "chair" and "share" , Compatible with most home and office telephones, Connects easily between handset and phone base, no wiring involved, Compact and portable, take it with you everywhere, Battery included.
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