Item #: Q34
Our Price: $1.39
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Versatile stopper that fits our 2000 ML Erlenmeyer Flask. Use as an airlock for yeast culturing, and even more useful as a sterile shield when preparing media. The proprietary foam is heat-resistant, and will withstand autoclaving or pressure cooking, making it an ideal flask plug when preparing sterile wort and agar. The honeycomb structure of the foam lets the plugged flask breathe, yet bacteria and wild yeast are filtered out and cannot reach the media. This means you can put your media in an Erlenmeyer flask, plug with a Foam Stopper, and pressure cook to sterilize, fully confident that bacteria and wild yeast will not enter the flask, even during the cooling and later storage period outside the pressure cooker.

Also great to use as an airlock for a 5 or 6½ gallon carboy. Just replace your stopper and airlock with the foam stopper. 2" diameter, 2 1/4" tall.


Average Rating:
(based on 5 reviews)

Showing 5 Reviews:

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by Jason Gray
on 1/12/2016
from Fresno, CA
Excellent Product
I have used this product for several years now. This stopper does a great job for all of my yeast starters on a stir-plate. I sterilize with Iodophor before using it with my 1000 or 2000 ml flasks. I also use the stopper to top my carboys when they are being sterilized, and  instead of an airlock after I have dry-hopped.  All positive with no negatives. 5 stars.
by Joseph
on 1/28/2014
from Kansas City
I use these instead of foil. They are easy to sanatize. I just feel a little afer using these.
by Jerry
on 2/21/2013
Excellent product
I have used this for over a year. Does a great job for all of my yeast starters on the Stir starter stir-plate sold here at Williams. I sterilize with Star San.  This is good for getting maximum yeast growth for a very inexpensive price instead of tin foil on the flask.  I use a 2000 Ml flask.  All positive with no negatives.  5 stars.
by Robert
on 3/24/2012
from North Reading
Easy to use
I put these on the flask during the boil so they are sanitized by the escape steam during the 15 minute boil time. Easy to clean, last through several batches. Never had contamination issues.
on 5/13/2011
from Massachusetts
Easier than multipiece airlocks.
I've done well with these stoppers in a flask for yeast starters.  I boil them before each use for sterility and they hold up nicely.
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