Shell for a 16oz Mason Jar for plants growing. This cover protects water from algae growing. Small vertical slot allows to see level of water in the jar. There are two versions of Shell Caps (Mason_Shell_Cap_02 and Mason_Shell_Cap_03). Select which one is better for your project.

The following things could be used with the Mason Jar: https://www.thingiverse.com/thing:3895629 https://www.thingiverse.com/thing:3895160 https://www.thingiverse.com/thing:3981269 https://www.thingiverse.com/thing:3932095