Rubber Stopper 12-H (35/45) drilled for air lock
Rubber Stopper with pre drilled hole for airlock. Suitable for plastic containers with 50 mm cap. Top end of the Rubber stopper is 45 mm, bottom end is 35 mm. Rubber stoppers is the prefered choice compared to fermentation caps since rubber always makes a tight fit without any leakage of carbon dioxide.
Drilled hole size: 8 mm