This is a ready made heat stick. You could use it to bring your mash or sparge water up to temp (or up to temp more quickly). You could also use it to help your wort get to a boil more quickly. There are plans available to make your own heat stick using things like water heater elements. At just over $40, this seems to be a bargain.
MARSHALLTOWN The Premier Line 742G Bucket Water Heater - $40.37 (Save 46%) + Free Shipping
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