With the link, all I did was copy the URL from the address bar and paste it between the URL tags to create a link (the URL tags are the last one of the 9 boxes marked B, i, u, Quote, code,List, List=, Img, URL at the top of the text box you type in when replying, click it one to open the URL, paste your link then click again to close it)
All I do with my cooler is insert the power cord 180 degs to change from hot to cold. As I say it is meant for the car, so I run it off a 240V AC to 12V DC transformer. As it has DC going in to it, it will be able to sense the plug direction, and thus heat or cool accordingly. There is no temp control on it; it just runs flat out so I control mine with an electric timer plug to cycle it on or off (thanks to Dr Dave for that suggestion!)
Afetr a bit of a search this may be the principle in play here...
http://en.wikipedia.org/wiki/Thermoelectric_cooling