Bormioli Rocco Fido 3.5" jar replacement gaskets, pack of 6. Simply use the replacement gaskets for airtight sealing to keep your fruit, vegetables, jams, and sauces perfectly preserved. For best results, dip rubber gaskets in boiling water first, then place onto jar lids. There is no need to buy new jars with your set of replacement gaskets on hand. Dimensions 3.5 diam. x .12H inches.