Uniden DECT1820 - Manual (Page 8)

Battery Information
Low battery alert
Cleaning the battery charging contacts
Caution:
If the symbol is displayed on the handset, "Charge Battery"
appears and you hear the low battery tone, you will need to
recharge your handset. We recommend that you place the handset
back on the charger between use to ensure that it is always fully
charged.
To maintain a good charge, clean the
charging contacts on the
handset once a month. Dampen a cloth
with plain water. Gently rub
the damp cloth over the charging contacts
until all visible dirt is
removed. Dry the contacts thoroughly
before returning the handset
to the cradle.
Do not use paint thinner,
benzene, alcohol, or other chemical
products. Doing so may discolor the
surface of the telephone and damage the
finish.
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