I purchased this unit to power theKoolatron Compact Kooler, which uses 4.5 amps. I figured since this adapter is rated at 5.8 amps there should be no problem. Well there was a problem. I got no juice from the adapter at all. At first I thought it was an issue with the cooler, but I quickly ruled that out when I was able to get the cooler running while plugged into a 12V outlet in my car.I then thought that maybe the amp rating of 5.8 was exaggerated, so I tried plugging in a standard car phone charger, which also did not work with the adapter. My conclusion ... the adapter is a dud. It seems like after reading some other reviews here, the amp rating of 5.8 may indeed be exaggerated, so I decided to go with another product (5 Amp AC to 12V DC Power Adapter).*** UPDATE ***The5 Amp AC to 12V DC Power Adapterworked great right out of the box. My first impression was that it was definitely much heavier than the Sunforce 55520 and it seemed to cool the fridge effortlessly. If you need an AC/DC Power Converter that will power a device upto 5 amps, skip the Sunforce and go with the5 Amp AC to 12V DC Power Adapter. You won't regret the decision.