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                    How long does the battery last?
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                    What should I do if the CF-100 doesn’t turn on?
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                    Can I replace the batteries, and what type of batteries does the CF-100 use?
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                    Can I use the CF-100 OxyKnight Finger Pulse Oximeter outside?
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                    Why does the display go out suddenly?
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                    Why aren’t measurements displayed on the mobile app when using optional Bluetooth?