No need to worry about having to buy a new container or spilling liquid everywhere if you lose or damage your existing spout just print another and your good to go.

The main spout was printed with Ninja Flex - Semi flex (92A shore hardness).

The O ring was printed with a 60A flexible filament - or you can source a production O ring with a 35 mm ID and 41 OD mm (or there abouts).

The disc is designed to fit inside the cap just in case you have lost that as well

The attached spout file has 1 mm walls which I have found represents, good wear characteristics, great flexibility and beautiful printing characteristics.

Printing tip: Adjust Slicer parameters so that main spout is printed with 4 concentric circles.

Please note: While this thing depicts the use of this spout in a portable fuel container there are state and federal regulations which govern portable fuel container- This thing is unlikely to be compliant and is not recommended for this purpose. Also the polymer used may impart impurities into your fuel mix.