20%
Porsche used the version of these with the mounts on the back. Please note that these are top/bottom mount and are most often used on Mercedes and Lamborghini's. However, enterprising owners have found ways to mount these on 911's. We carry them here as they are about half the price of the back mounts and usually available while the back mounts can be hard to find at times.
You will find the correct Best-in-Class Hella 139 fog lights HERE. Not always available.