CM Mason, Ball, and Kerr Jar Reusable Regular Mouth Food Grade Silicone Seals (12ct) SILICONE SEALS are the best seals for any brand wide mouth plastic caps on the market guaranteed! They are wide enough that they cannot fall out while putting the plastic lid on the jar and provide an airtight fit. Easy removal for easy clean; clear silicone aids in cleaning inspection. Seals are BPA-free Food Grade; includes Seals only; lids not included Regular Mouth dimensions are 2 1/16 inches inner diameter and 2 3/4 inches outer diameter.