Please note that a car 12Vs socket is able to supply many more amps than the 0.45A this unit can supply.
Unfortunately being the impatient Amazon buyer I am, I bought it as soon as I saw it, not considering anything to do with power limits. Plugging into my xenon car lamp saw it break in under 5 seconds, and that was that.
Please also note that the build quality of the item itself is pretty shoddy, but I guess you're only spending a few pounds!
Fine for small gadgets like Sat Navs and flashlight chargers - but you need to spend more money if you have something bigger to power.