Fog Lamp Diameter?

[mpentico]

Has anyone actually measured the diameter of the GT fog lights?
(No guessing or estimates)

I'm looking for a H-4 (hi/lo beam) lamp upgrade.

There was a post several months ago by a guy who used V.W. headlamps, but I'm looking for a direct replacement.

 

[tapd117]

Sylvania is coming out with a silver star bulb ST 9145. The part shows at Advance Auto Stores but not currently in stock.

GG