100 Quart… 25 Gallon Coleman Xtreme Wheeled Cooler. This cooler is said to keep ice for up to 5 days in temperatures up to 90 deg F. Hinged lid, four cup holders, two handles and sturdy wheels. 36.5L x 16.75W x 18.25H in.
At 25 gallons this would make for a large mash tun.
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