There are 3 main differences between the Volt HID kit
and the Xtreme HID kit
The Xtreme kit comes with a 3 year warranty, has a relay harness allowing you to power the ballasts from the battery and the ballasts use authentic German parts similar to that of many OEM HID applications. It's our premium HID kit.
The Volt HID kit comes with a 2 year warranty and does not come with a harness so you power it directly from your OEM harness.
At the end of the day you really can't go wrong. Both are 35W kits and you get a $25 discount on either kit with the "JG" coupon code. You also get a free harness with the Volt kit with that same code.