6 metal wide jar lids (without rings)
Two air exchange holes with 0.2 microns Laminates of non-woven polypropylene with PTFE, give your mycelium enough fresh air and prevent any kind of contamination
20mm butyl self-healing rubber stopper for inject liquid mushroom cultures
reusable and highly durable
 
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When doing high pressure cooking, you need to loose lid about a quarter turn. Otherwise, the high pressue inside jar will push the stopper out.
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