PROMOTE FERMENTATION & PREVENT OXIDATION: Our twin bubble airlock can emit carbon dioxide for honey, white wine, milk wine alcohol fermentation and prevent oxidation. SIMPLE TO OPERATE: Easy for you to operate, simply fill water into the exhaust valve, insert it to the cover of the brew barrel or rubber plug on the top of the fermentation container and then cover it with the lid. CLEAR TO VIEW: Transparent plastic fermentation airlock enables you to clearly look inside, so that you can see the airlock do the hard work for you all the time. AUTOMATIC FERMENTATION & REUSABLE: The whole fermentation process is automatic, no manual control required, and it can be also repeatedly used for a long time. GREAT APPLICATION: The twin bubble airlock is suitable for pure juice fermentation, such as white grapes, honey wine fermentation, red wine secondary fermentation, etc. Hurry up and let your friends taste your own brewed bar at the party