D5S 35W OEM Replacement Bulbs - 50% brighter than OEM
D5S HID bulbs are the latest in D-series OEM replacement HID bulbs. D5S 35W OEM Replacement HID bulbs are 50% brighter than the factory 25W OEM HID bulbs. Direct OEM replacement bulbs have a built-in igniter and ballast.

D5S 35W with 42W ASIC Ballasts HID kit - 100% brighter than OEM
The other D5S HID bulbs are NOT direct factory D5S replacement bulbs. These are to be used with after-market ballasts. A D5S HID kit with 42W ASIC canbus ballasts offers 2x as much light as the 25W OEM HID bulbs.