Soldering In Plain Headers - Adafruit Feather M4 Express Manual

Finally, there's the "Stacking Header" option. This one is
sort of the best-of-both-worlds. You get the ability to
plug into a solderless breadboard and plug a
featherwing on top. But its a little bulky

Soldering in Plain Headers

Prepare the header strip:
Cut the strip to length if necessary. It will be easier to
solder if you insert it into a breadboard - long pins down
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