Fermentation kit Includes - 4 lead free glass weights; 4 BPA free water airlocks; 4 wide mouth lids with silicone gaskets; The kit uses water airlocks, the top cover is opened, and the right amount of water is injected to block the air from entering. The gas produced by the fermentation inside the Jar can be easily vented. KUNNV food-safe glass is lead free and non-porous so it never absorbs food odors, flavors or colors. Weight approximately (195 g), large and heavy enough to keep vegetables submerged below brine for best results of fermentation. The lids are one piece won't rust. The lids have a silicone ring/seal underneath to make things airtight, the airlocks and gaskets are just right for fermenting anything! Glass weight is easy to break. If the item you received is damaged, please contact us immediately for a free replacement.