In the cold winter months, ambient temperatures may not be ideal for beer and wine fermentation. Enter the fermentation brew belt! This handy device wraps around a fermenter and can maintain a temperature of 75F for up to 8 days. This has a 6 foot long cord that plugs into a standard 110v outlet. Will work with standard 5 and 6 gallon plastic carboys, 6.5 and 7.9 gallon plastic fermenting buckets. It is not recommend to use this with glass fermenters.