I know there was some debate regarding Hankook tyre markings.
Please note that the approved compound number for Clubmans is C9.
A second number (eg C91 or C92) does not signify a different compound.

Could you explaine why the tyres on the website are C5?

I don't know a lot of the Hankook tyres but if they are to be used for Proto next year it would be great if the exact tyre and compound would be open for us to read in the regulations.

What's the difference between C9 and C5?

Here's the extract from the 2015 regs;

"The only permitted tyres are (save as provided below) Hankook slick and wet tyres in the following sizes, with compounds and tread pattern as approved by the Clubmans Register:

Front: 170/515R13 Rear: 210/570R13

Or such other Tyres or specification of tyres as may be specified from time to time by the Championship Organisers and the Clubmans Register.

The sole suppliers of Hankook racing tyres to the Championship are:
Hankook Motorsport, Mr Tyres (Motorsport Ltd.), Unit B, 33 Pitsford Street, Hockley,
Birmingham, B18 6LJ
Tel: 0121 551 4589 "

The approved slick compound is C9, which is widely used in single seater applications such as Euro F3 and MSA Formula.
To the best of my knowledge C5 is a much harder compound and not one we considered.

Thanks, i thought C9 might be for the rain tyres but this exlpains enough for me.