Great Value : Including 4 stainless fermenting lids,4 silicone seals,5 silicone stoppers, 4 BPA free airlock
Compatibility: Works on Mason jars with standard wide mouth lids (3.38"/86 mm diameter).Fit small 4oz wide mouth jars all the way to large 64oz wide mouth jars for fermentation
Date Mark: You can mark with fermenting date and name on the lid
Food Grade Material: SUS 304 stainless steel lid, food grade silicone ring gasket and BPA free 3-Piece airlock
Innovation Stoper Design : Once fermentation was complete, just remove the airlock and seal the hole with the silicone stopper