Review on 🔒 3ct. - Set of 3 Cylinder Airlocks with #6.5 Stoppers by Amy Perry

Price is right. They don't want to stay safe in my 1 gallon jar without tape. In retrospect, I should have ordered a cork along with a jar of a certain brand. But if you have a couple of mismatched gallon jugs and don't mind using duct tape to make sure it really sticks, I would recommend this product. Advice! Be sure to dry the inner rim before inserting the stopper, if wet it will pop out. My understanding is that gallon jugs typically use a stopper with the number six, which is six and a half.