What an upgrade to the traditional clear vinyl gaskets! Reduce issues with leakage, ensure a great seal, and reduce your worries about storing wine in a variable volume tank. These white, food-grade, rubber gaskets are formed like a channel as opposed to a circular tube to form a better seal against tank and lid. Nearly 3x as thick as the clear vinyl gaskets they also help to reduce oxidation. Hold one of these in your hand and you will instantly know from the hefty weight that this is a worthwhile upgrade for every variable volume tank owner who plans to store wine.