3/8" NPT X 1" Hose Barb Fitting

This is an NPT adapter that you will probably not be able to find at your hardware store, at least not easily. It adapts 3/8-inch NPT to 1-inch ID hose.
I designed a single-barb adapter and a 3-barb adapter. I included a solid and and hollow version. The solid version may be useful if you want to drill a single diameter hole through the adapter.

I usually have to scale by 10 all my drawings when they go into my slicer. It maybe because I draw them in mm and slicers may expect cm.