Entry-level inexpensive airlock aka twin bubbler. Works great for wine or beer. Fill approximately halfway with water. The water acts as an environmental barrier keeping bugs and oxygen away. Also prevents converting ethanol alcohol to cider/ acetic acid. Preferred choice for fermentation. We can attach it to any fermenter.

Add some water and stick this on top of your fermenter vessel or carboy. Then wait for the magic to happen. This time tested traditional airlock releases the CO2 produced without outside air contaminating your brew. It prevents oxidation, acetic acid/vinegar creation and hence, preserves the aromas of your homemade beverages and anaerobic ferments.

The airlock is made of plastic and fits any 9mm hole/aperture. Please use an appropriate sized cork/grommet (the black ring in the picture to be purchased separately) to attach to your fermenter. Read the article on how to prevent oxidation of your homebrew.

Dimensions: Length 165mm, thickness 11mm

Adding some spirit or food-grade disinfectant in the airlock helps keep bugs and bacteria away. Besides, if using for secondary, please check the water-level in the fermentation every 2 weeks to prevent it drying out. Alternatively, you can also use 3 piece airlock.

A couple of points to remember:

1. If the temperature variation is too high, airlock might end up sucking air instead of letting it go.
2. Properly check the leakage in your drilled hole/bung on your fermenter to prevent leakage.
3. Freezer/fridge leads to accelerated moisture loss. So check the moisture level frequently.
4. Adding some salt/alcohol will prevent the liquid in airlock from freezing.