Dry box connector for multiple layers.

Printed this for TPU storage, and wont be making a BCMU. As i didnt have any cake boxes i used a SmartStore box. Saw it was alot of empty space and wanted it stackable. I therefore redesigned a plug mimicking the Hygrometer with the screw holes on the bottom for mounting to the next. I only use 2 in height but i am pretty sure its sturdy enough to go all 4 if needed.