PLEASE CHOOSE YOUR PREFERABLE VARIANT AND DELETE OTHER male couplers
ALSO, PERFORM A CUT FUNCTION on male coupler FOR YOU PREFERABLE WALL THICKNESS
 

for X mm thin wall: use CUT function in Bambu Slicer at height of X + 6,5 mm

print slowly at 0.1mm layer height

Fits walls up to 12mm thin.
Fits into standard 8mm hole. Female coupler can be swapped for standard M8 nut.
For variants Standard 1.75 mm and Standard 2.85 mm you will just need to put filament through.
For variant 1.75mm with PTFE insert you will need to insert PTFE tube with length of your liking.

Can be seen on my drybox project:
https://www.printables.com/model/253774-efficient-filament-dry-box