you need to go to halfords and get the mains power kit which is basically a box that you plug into the mains and then it "drops" the power down to 12v it has a ciggy lighter socket on it and then you plug your coolbox lead into that.
It depends on your coolbox. Some are only 12v, in which case you will need a converter (Maplin are much cheaper than Halfords). If it also has a 240v plug, then you only need a hook-up lead, but make sure you get a proper one with fused sockets, rather than one of the dodgy Ebay ones.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets