Rubber Airlock Grommet – 3/8″ ID

This rubber airlock grommet is a simple, clean way to install an airlock directly into a bucket lid or other container without needing a full-size bung. Instead of drilling a large hole to fit a #6.5 stopper, you can drill a smaller hole and press this grommet into place for a snug, professional finish.

With a 3/8″ inside diameter, it’s perfectly sized to hold standard plastic fermentation airlocks securely. Once installed, the grommet creates a tight seal around the airlock stem, allowing CO₂ to escape while keeping oxygen and contaminants out.

This is an especially useful solution if you’re modifying:

• Plastic fermentation buckets

• Smaller bucket lids

• Wide-mouth jar lids

• Custom fermentation vessels

Because the grommet stays installed in the lid, it’s convenient and always ready to go. Unlike a removable bung, there’s no need to fit or remove a stopper each time. It’s a great option for anyone who prefers a cleaner, more permanent setup.

Made from flexible rubber, it presses easily into a properly sized drilled hole and holds firmly in place. It’s a small part, but it makes fermentation setups simpler, tidier, and more reliable.

Specifications:

• Inside Diameter: 3/8″

• Designed for standard airlock stems

• Ideal for bucket and jar lid modifications