I've just ordered depo projector headlights with black inners and received my hid kit d2s-and-d2r-35w-proplus-xenon-conversion-kit from hid4u thinking it would have slim ballast, but no, is there much difference between slim and normal size ballasts and would they fit or should I should get the slim ballasts?

Edited 8 April, 201412 yr by Roddit Vrs

No difference performance wise, the slim ones are just easier to hide and tuck away. There should be some images on the website of the size difference? Or Google?