I thought it used to be 17% but now the rule was no tint at all forward of B pillar. Load of bollocks really as the law was based on one accident with a motorcyclist and a car with limo tints on the windscreen and front windows. Don't see a law saying you can't wear sunglasses after dusk while driving.. though that's just a matter of time given the penchant of labour for trying to legislate every single waking minute of our lives (and that's just till they can get our dreams on a database). Thank fcuk we have the SNP here in Scotland, at least we have an alternative to the bollocks those down south are stuck with. Not brilliant but the better of two evils and one no-hoper.
God, I'm getting ranty in my old age.