This air limiting cap was designed for competitive swimmers with Finis Snorkels that need to limit their air flow while swimming with a snorkel. Many swimmers tend to either buy a hard plastic snorkel cap or tape off the top of their snorkels to limit airflow.
Best if printed in a flexible plastic (NinjaFlex!) and should fit most snorkels. If printed in PLA or ABS you may have to scale it slightly for a good fit.
For Printing I printed this upright. The top is at an angle and should print fine.
Also I printed in on a Makerbot Replicator 2 in NinjaFlex with the following settings:
Print Speed - 45mm/s
Temp - 230C
Perimeters - 3
Infill - 100%
I will be uploading designs that fit better using PLA/ABS instead of NinjaFlex.