I have just had a letter from the International Security Register confirming that my new Octy is on the register, and asking for some additional details.

One thing requested is the locking wheel nut code.

I have had a look at the "key" and it has a 2 digit number stamped on the end. Is this the code or just a part number?

If not the code where do I find it?

If it's anything like the locking nuts on my Fabia Elegance, the two characters refer to which of the profiles you have actually got. So part number + this code describes the key for your car.