Factory tints - UV protection or just cosmetic?

[Pionir]

I've got a Ford ST220 and like most "modern" cars, it's got factory spec tinted windows (probably 20% ish) but there's no stats on UV protection.

Does anyone know if the factory tints offer any UV protection? I'm just wondering if it's worth getting an additional film tint applied which will give me UV protection.

Cheers, David