Shop Our Categories Oak Barrels, Ltd. View cart Call Us: (888) 926-2555 Worldwide Shipping! SHOP Oak Barrels Black Hoops Galvanized Hoops Vinegar Barrels Toasted Vinegar Barrels Un-Toasted Vinegar Barrels Mother of Vinegar Specialty Barrels & MORE Cork Coaster Set - Set of 8 Tequila Barrel Gift Set Vanilla Extract Barrel Kombucha Barrel Age Your Own Balsamic Kit the 'Perfect' Little Funnel Twin Bubble Air-Lock with 3/4" Rubber Stopper Replacement Parts Testimonials Info Center Instructions & Barrel Prep Barrel Dimensions & Conversions The Angel's Share & More Thoughts on Making Vinegar Contact Us General Barrel Inquiry Business Barrel Inquiry Close Search Submit search Nav Menu 2 Nav Menu 3 Nav Menu 4 Nav Menu 5 Nav Menu 6 Nav Menu 7 Nav Menu 8 Home > SHOP > Specialty Barrels & MORE > Twin Bubble Air-Lock with 3/4" Rubber Stopper > Twin Bubble Air-Lock with 3/4" Stopper Regular Price: $6.95 On SALE Today: $4.95 Savings: $2.00 Product Code: TBA Qty: Laser Engraving Options Overview Your Twin Bubble Air-Lock will arrive complete with 3/4" rubber stopper designed to fit snugly in either our 10L or 20L American oak barrels. Let the Percolating Begin! An air-lock, sometimes called a fermentation lock - is a small device used in brewing beer or in making wine. When filled partially with water, it acts as a water trap allowing carbon dioxide to be released. When inserted into the bung of the oak barrel, it allows the gases caused by a fermentation to literally percolate through it and then, out of the barrel. Air-locks also play a vital role in protecting your wine or brew during 'secondary fermentation' when the contents become most susceptible to contamination from outside sources. It's easy to use! Simply attach the air-lock by placing its stem into the hole of the rubber stopper and then place the rubber stopper into the 3/4" bung hole of the oak barrel. After you have the air-lock in place, fill it approximately half full with water. Be sure to put the cap back on the air-lock. The cap has tiny pinholes that allow the gasses to make their way out. Share your knowledge of this product. Be the first to write a review »