Rechargeable Hearing Aids In-ear Mini Invisible Sound Amplifier Ear Aid Adjustable Tone

Description

Normal operating conditions:Ambient temperature 5 ? ~ 40 ?;Relative humidity ? 80%;Atmospheric pressure 86kPa ~ 106kPa;Power supply voltage d.c.1.4V, with a relative error of +5%, -10%.Appearance and structureHearing aids should be fully assembled parts, fixed should be reliable; text, symbols or markings should be clear, accurate, solidPositive and negative power supply contacts should be effective.The gain control operation of the hearing aids should be flexible and reliable, and the fastening parts should be free of loosening.Electro - acoustic performanceOutput sound pressure level (OSPL90) at input sound pressure level of 90dBMaximum OSPL90Shall not exceed 118 + 3 (dB)