6 Gallon Glass CarboyThis 6 Gallon Glass Carboy is airtight, easily sanitized, and does not hold an odor, perfect for the primary or secondary fermentation of beer or wine. Glass carboys can be preferred to plastic buckets and plastic carboys because they are made of heavy duty glass and won't scratch like plastic or break down over time. If handled carefully, a glass carboy will last decades while giving the same great performance for every beer or wine fermentation.