Can you let me know what the part number is for this adapter?
The cheapest one I can find in Maplin is £24.99 on Promo (saving £20)


I've just spotted one on the Walmart website at $49 that is made by APC

Converts DC power to AC
Plugs directly into an airline's power receptacle or car's cigarette lighter to power your electronic devices
Features automatic shutdown to protect your car's battery power from fully draining
Special adapter for use on both types of airline power ports
Status indicator LEDs alert you to the unit's power status
Built-in protection from surges and spikes
75-watt power limit
Still half the price of the first one we saw in MCO