This is a model of phone that might best fit seniors. With a battery capacity of 800 mAh you can make quite a few phone calls before the battery dies.
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Nokia 105 (2019 edition) 1.77 Inch UK SIM Free Feature Phone - Black
Clove Technology
Nokia 105 (2019)
Comet
Nokia 105 (2019 edition) 1.77 Inch UK SIM Free Feature Phone (Single SIM) – Black