For added security i have a disklok full steering wheel lockable cover. Bought it from eBay as used – it was cheap because it only came with one key but new keys are available from disklok for £14 see https://www.disklokuk.co.uk/contact/replacement-keys/
The small size fits our Peugeot wheel fine which is the most popular size.
It makes a great visual deterrent as well.
A bit too large to take on travels – only used when stored on our driveway when the motorhomes is not in use.