Our host sells both types of bulbs -- you first need to determine whether your headlights take h1 or h4 bulbs -- h1 headlights need two bulbs apiece, h4 headlights only need 1
Porsche 911 & Carrera Lights and Lenses - Page 1 will get you to our host's h4 bulbs,
Porsche 911 & Carrera Lights and Lenses - Page 2 will get you to h1 bulbs
it's ALWAYS a good idea to install a headlight relay while your at it -- from the factory, all headlight current runs through the turn signal switch, the relay will bypass this and help keep the switch from failing relay kit link"
Pelican Parts - Product Information: JWST-911-HLPR