Still, such claims are making premium-priced halogen bulbs an alluring choice ... and dual-filament (H7) bulbs from GE, Hella, Philips, and Sylvania, and PIAA's dual-filament bulb.

and the size you need depends on whether you have halogen or HID headlights. Some examples are H4, H3, H1, H7, H10, and H11 for halogen and D2S, D1R, D3R, and D4R for HIDs. Make sure you have the ...