What's the difference between the c1 and c5 bodykit

[Weston]

Hey guys, I have a 2006 toyota vitz rs and I was wondering what is the difference between the c1 and c5 rear lip part of the bodykit because they both look similar however I know for a fact that the c1 fits the yaris and c5 fits the vitz however I would like to know if the yaris c1 would actually fit the vitz rear or if the yaris has a shape which is too different.