Fourpiece set of Sshape twinbubble air locks with plastic grommets, designed for homebrew fermentation of wine and beer. These air locks provide a simple, reliable way to let fermenting CO2 escape while preventing oxygen, dust and contaminants from entering your vessel. Key benefits Protects your fermenter: vents CO2 safely while maintaining an airtight barrier against oxygen and airborne contaminants. Easy visual monitoring: twinbubble Sshape design makes fermentation activity easy to see at a glance. Ready for multiple batches: four complete units let you equip several fermenters at once or keep spares on hand. Simple to use and maintain: pushin plastic grommet provides a secure seal; air locks are easy to fill, empty and clean. What's included and how it works Package contains four Sshape twinbubble air locks with matching plastic grommets. Fill the air lock partially with water or sanitizer, insert the grommet into the fermenter bung or stopper hole, then snap the air lock into the grommet. As yeast produces CO2, gas escapes through the Sshape channels; liquids or contaminants cannot enter back into the vessel. Key attributes Configuration: Sshape, twinbubble design for clear visual fermentation indicators and effective gas flow. Material: durable plastic construction for lightweight, chemicalresistant performance and easy cleaning. Contents: set of 4 air locks with plastic grommets. Functionality: allows oneway release of fermentation gases, helps maintain an anaerobic environment. Compatibility: designed for use with homebrew fermentation vessels that accept a grommetstyle air lock (commonly used with standard bungs and stoppers). Performance and care Reliable seal: the included plastic grommet ensures a snug fit to reduce leaks and contamination risk. Reusable: rinse and sanitize between batches; plastic construction resists corrosion from sanitizers and typical brewing conditions. Simple maintenance: disassemble for cleaning, rinse thoroughly, and sanitize before each use. Use cases Home wine fermentation: monitor primary and secondary wine fermentations while keeping the must protected from air exposure. Home beer brewing: use on fermenters and carboys during active fermentation to safely vent CO2 and watch activity levels. Multiple fermenters or backup units: equip several vessels at once for batch brewing or keep spares ready for quick replacement. Practical tips Partially fill the air lock with clean water or a recommended sanitizer solution to create the liquid seal. Check periodically for blockages or excessive foaming; clean and sanitize between uses. Keep spare air locks from this 4piece set on hand to swap out if one becomes clogged or damaged. A straightforward, costeffective accessory for homebrewers who want a clear, reliable way to monitor and protect fermentations of wine and beer.