Drilled gum rubber stopper. Used to provide a positive seal on fermentors. Drilled hole is compatible with standard airlocks.

Compatible with: older models of Big Mouth Bubbler® EVO 2 w/screw-on lid & Little Big Mouth Bubbler®
Drilled gum rubber stopper. Used to provide a positive seal on fermentors. Drilled hole is compatible with standard airlocks.

Top Diameter: 1.048"
Bottom Diameter: 0.909"

Compatible with: older models of Big Mouth Bubbler® EVO 2 w/screw-on lid & Little Big Mouth Bubbler®