FermentArmour Carboy Sleeve. Made of Durable Neoprene for 6 gallon / 23 liter Glass Carboys.  Extra strong.  Carboy not included.  Includes three handles for moving and pouring.  Protects beer against harmful light and guards against temperature swings.

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FermentArmour Carboy Sleeve made of Durable Neoprene for 6 gallon / 23 liter Glass Carboy – Ideal brewing equipment for homebrewers and winemakers – bring your beer kit to the next level

Also: Kegco KC FP-CB-06 Glass Carboy, 6 gallon, Clear – via Amazon

Also: Yeast Starters & Fermentation Resource Page | Hands On Review Mark II Keg and Carboy Washer