Plug for 3/8" hole

INTENDED TO BE PRINTED IN TPU. Recommend at least 3 walls when printing these.

Just a plug designed to fill a 9.5mm hole in the side of a 55 gallon drum. I did not realize these drums are not uniform thickness when installing some horizontal chicken waterer nipples. In some places, the thickness of the drum was so substantial, that the threads of the nipple did not stick through enough to tighten a nut on the back. Hence I designed this plug.

Lil'Clucker Horizontal Chicken Waterer Nipples https://www.amazon.com/LilClucker-Horizontal-Chicken-Waterer-Automatic/dp/B0BXX1LNFM/ref=sr_1_16?crid=1BR6KGNTE0JJC&keywords=lil+clucker&qid=1706127756&sprefix=lil+clucke%2Caps%2C101&sr=8-16