Feature●10 PIECES OF RINGS: 10pcs grommets for 15L 25L 30L and 60L of homebrew digester.●PNEUMATIC RING: Airlock ring for airlock on homebrew beer fermenter beer wine lid.●HIGH QUALITY PLASTIC MATERIALS: Made of high quality plastic material, and having long lifespan.●FIXED AIR GATE: Use with airlock for fermentation, perfect for securing airlock during fermentation.●BEER BREWING TOOL: It will help maintain the ferment for a longer period, practical tool for beer brewing.Description