This may be a dumb question but, I searched all over for this but couldn't find any answers. What do the bulb numbers mean, like the H1, H3, H4, etc.?? If you don't know what I'm talking about, click this link and scroll down to the Apexcones, click the drop down box for bulb type.

http://understeer.com/onlinestore-lighting.shtml

Thanks.

the shape of it, if you have
us headlights - 9006 low beam
euro headlights- h1 low beam
foglights- h1