We have the Camco one. It works ok, seems to help with keeping things cold. However, there's no on/off switch on it. So the only way to shut it off after a weekend of camping is to pull the back off so it breaks the battery circuit. So this thing is now sitting on top of the fridge until the next trip in 3 pieces: the front, the back, and the charcoal pack. Poor design if you ask me.