If you have a rubbish local Fiat dealer then its easier to take a model number with you.
735411040 (Black) (matt black MY06-MY07)
735416283 (Graphite) (light gray metallic MY08 and MY06 Sport previous models, ...)
735448077 (Dark Graphite) (Gray metallic black MY07-MY08 Active Dynamic?)
Not sure there all 100% right my fascia is in the post should be here tomorrow .
If you have a t-jet sporting its the normal graphite I think as I purchased a dark graphite and it was too dark.