A simple, reliable airlock solution for homebrewers and winemakers. This 2piece twinbubble airlock with cap includes a #6 rubber stopper and grommet design to let fermentation gases escape while keeping contaminants out. Designed for straightforward installation and easy cleaning, it's a practical accessory for smallbatch beer and wine fermentation. Key benefits Controls pressure and prevents contamination: allows CO2 to escape during active fermentation while blocking outside air and airborne microbes. Easy to use and maintain: twopiece construction separates for quick cleaning and inspection. Complete starter set: comes with a #6 rubber stopper so you can install the airlock right away on compatible fermenters. Visual fermentation indicator: twinbubble design makes activity easy to see so you can monitor fermentation at a glance. Secure fit: grommetstyle connection keeps the airlock sealed during fermentation. What's included 2piece twinbubble airlock with cap #6 rubber stopper (grommetstyle fit) Key attributes Functionality: Twopiece airlock vents gas, prevents backflow/contamination, and reduces the need to frequently open the fermenter. Compatibility: Supplied with a #6 rubber stopper for direct fit on fermenters that accept that stopper size. Design: Twinbubble airlock design provides a clear visual cue of fermentation activity and allows for easy assembly/disassembly. Performance: Reliable gas release with a secure grommet seal to maintain an anaerobic environment during fermentation. Included cap: Provides an additional seal when needed (for transport or when fermentation pauses). Simple installation and care Insert the #6 rubber stopper into the fermenter's opening. Push the airlock into the stopper/grommet and add a small amount of water (or sanitizer solution) into the airlock chambers. Snap the cap on when a tighter seal is needed or during movement. Disassemble the two pieces for rinsing and sanitizing between batches. Common use cases Homebrewing beer: Monitor active fermentation, allow CO2 to vent, and prevent contaminants from entering primary or secondary fermenters. Winemaking: Maintain an anaerobic environment during primary fermentation and observe fermentation progress without opening the vessel. Smallbatch fermentation: Ideal for hobbyist setups—mead, cider, or experimental batches—where a simple, reliable airlock is required. Practical considerations Verify your fermenter accepts a #6 rubber stopper before installation. Keep the airlock and stopper clean and sanitized to avoid introducing microbes. The included cap is useful for temporary sealing when moving or storing your fermenter. A straightforward, nofuss airlock and stopper combination that supports safe, visible fermentation for homebrewing and winemaking projects.