Huawei U3900 User Manual page 46

M-Ratings: Phones rated M3 or M4 meet FCC requirements and
are likely to generate less interference to hearing devices than
phones that are not labeled. M4 is the better/higher of the two
ratings.
T-Ratings: Phones rated T3 or T4 meet FCC requirements and are
likely to be more usable with a hearing device's telecoil ("T
Switch" or "Telephone Switch") than unrated phones. T4 is the
better/higher of the two ratings. (Note that not all hearing devices
have telecoils in them.) Hearing devices may also be measured.
Your phone meets the M3/T4 level rating. Hearing devices may
also be rated. Your hearing device manufacturer or hearing health
professional may help you find this rating.
This phone has been tested and rated for use with hearing aids for
some of the wireless technologies that it uses. However, there may
be some newer wireless technologies used in this phone that have
not been tested yet for use with hearing aids. It is important to try
the different features of this phone thoroughly and in different
locations, using your hearing aid or cochlear implant, to determine
if you hear any interfering noise. Consult your service provider or
the manufacturer of this phone for information on hearing aid
compatibility. If you have questions about return or exchange
policies, consult your service provider or phone retailer.
To ensure that the Hearing Aid Compatibility rating for your device
is maintained, secondary transmitters such as Bluetooth and/or
Wi-Fi components must be disabled during a call.
For more information about the FCC Hearing Aid Compatibility
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