Ball Jar Wide Mouth Fermentation airlock

thingiverse

This is a basic fermentation lid for wide mouth ball jars. You will still need the ball jar rings. For an even tighter seal, consider adding a rubber o-ring or food-grade silicone gasket between the jar and the lid. Simply add water and secure the cap in place. Always ensure the water level remains at least halfway full. You can also use nail polish to mark the cap, making it easy to see when the water level has dropped too low.