This shield has 4 features that are very desirable:
Protection from cold
keeps your beer or wine warm when your carboy is stored in cool conditions.
Protection from heat
keeps your beer or wine cool when your carboy is stored in overheated conditions.
Protection from light
keep your beer or wine warm from the harmful effects of UV (Ultraviolet) light.
Protection from damage
helps to keep your carboy from making contact hard surfaces.
Eliminates the need for less effective or cumbersome blankets, carboy sacks, plastic sleeves and rubber bumpers.