Instructions:This is taken from their email (given to me by a colleague):
Secure Airport Car Parking at
EDINBURGH GLASGOW PRESTWICK
Even if you have used your code already, please feel free to use it as many times as you wish and forward it to friends, colleagues and family so they can benefit from a discount as well. If you have lost your code, please e-mail us at [email protected] and we will send you another.
Always useful considering that the prices for airport parking are so high. This may make them at least bearable :)