You can go to any autoparts store and let them know what kind of car you own and they will supply the proper bulb for you. They range in price from around $10 to $35. You can also find them online at sites like autozone.com or advanceautoparts.com http://www.partsamerica.com/ProductList.aspx?parttype=301&ptset=A&searchfor=Headlamp
Your owners manual will specify all of the replacement bulbs for you your van. I believe it would be a 9006, but it could be a 9005, H4, etc.
same that came out [ possible 9004hd] or you up grade both sides sylvania pure whites , ask your parts suppier napa, advance, pep boys, auto zone,ect. theyn can help
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