3 x AAA Battery Holder connects 3 AAA batteries together in series for powering all kinds of projects. The box is slim, and 3 AAA's add up to about 3.3-4.5V, a very similar range to Lithium Ion/polymer (Li-Ion) batteries and have an on-off switch. That makes the holder ideal for use with 3.3V projects.
3 x AAA Battery Holder fits any standard AAA battery. When using rechargeable NiMH the output voltage will range from about 3.7V with charged batteries to 2.7V at the end of life with a nominal voltage of 3.6V. When using alkalines, the output will range from 4.6V with new batteries to 3.3V at the end of life with a nominal voltage of about 4.5V
Adafruit Learn Link: https://learn.adafruit.com/battery-powering-wearable-electronics
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