Gamma Seal Lid by Gamma 2, Inc, Gamma Seal Lids [Hands on Review] are used on conjunction with standard sized 3.5 to 7 gallon buckets and are popular for grain storage. My rule of thumb for grain storage capacity is 5 lbs per gallon. With that estimate 50 lbs fits in (2) 5 gallon buckets.
Gamma Seal Lids are a great upgrade. You attach the base of the unit to the bucket and leave that intact. The lid screws on and off easily. No more prying lids off. These are also airtight. I use buckets with Gamma Seal Lids as my primary storage for bulk grain and recipe kits.
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