M5GO BOTTOM is apparently the bottom part of M5GO which is a upgrade of basic bottoms, with a larger battery(500mAh),Analog Micphone, LED Bar , two more HY2.0 PORT(PORT B/PORT C)，and more. Its back is compatible with Lego holes, and the pogo pin can be used to connect to supported I2C devices (such as BALA) or magnetic charging bases.
M5GO/FIRE Battery Bottom Charging Base
precise product, high capacity - in deep sleep mode keeps the M5stack running for over 1 month
Product arrived on time and in perfect order. Thank you very much.
The unit arrived and works. I'm a little upset that the original unit only lasted 3 months