From the technical details of a multimeter:

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> AC Voltage: - Range and Accuracy: 200mV ± (1.0%+2); 2V ± (0.7%+3); 20 ± (1.0%+3); 200/600V ± (1.2%+3) 
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What does the notation "± (0.7%+3)" mean? Specifically, what does "+3" mean?