Lamin-x is a proper film that goes over the will make your head light beam yellow as well and is not road legal
flyeye is a alternative but does not look as good but is road legal and does not change the colour of your head light beam.
Are yellow headlights not legal? They use them in Europe n most of our car manufactuer UK spec is based on euro legislation.
I know they're the preferred colour for fog...and of lots of people who use them hassle free.
If in doubt. Email the dvla/vosa, its been done before and you get a definate answer you can use in court if you get in trouble.
Personally if your not dazzling others, and actually have two headlights unlike far too many people. Then it should be legit!
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