This 6.5 Gallon plastic fermenter is the ideal Size for brewing up two or more batches at the same time. The lids installed rubber grommet makes it easy to have an airtight seal for long-term storage. Buy a few extras so you can make multiple batches. These fermenting buckets are easy to clean, durable and versatile, with gallons marked on the side, so you can view How much liquid is in the fermenter. 6.5 Gallon Size. Pair it with rubber grommeted lid to ensure an airtight seal. Gallons noted on side of bucket so you know How much liquid is inside.