RCT1260
A GB sticker/plate is a legal requirement when travelling on the European continent, and you could get an on-the-spot fine if you do not have one displayed.
The Ring RCT1260 GB Magnetic Plate meets all of the requirements needed for it to be within regulation. It is easy to apply and take off of your vehicle, with no damage done to the vehicle's paintwork.
The countries in which you would need one are France, Belgium, Germany, Spain, Italy, Netherlands, Austria and Switzerland.