One of our Nalgene lids lost in a heated altercation with our dishwasher.  This is a clean-sheet design that functions and seals much like the original.

I printed this cap with the opening down and with supports (manual set) under the inside-center section of the lid only.  Based on the filament selected the threads shouldn't need supports.

Please select an appropriate and safe filament for your application/use case.

https://bmc.link/DKonneker