In a quick explaination. It moves heat from one side of the pad to the other using electricity and the peltier effect. It can be used to cool things below ambient (room) Temperature. I'm not exactly sure how you use a pad like that. I suppose you could hook it up to a water cooling radiator for a computer too cool the water. I have heard that it has problems with causing condensation so it is not suitable for use on most electrical components without some expensive modifications.
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