H4/9003-same thing
PIAA goes by H4, Sylvania goes by 9003. I would recommend the PIAA's, they have never failed me, but nonetheless read this forum its about those bulbs:
http://www.clubcivic.com/board/showt...ilverstar+piaa
Check out this site for the size--
http://www.sylvania.com/ConsumerPro...placementGuide/