HID comparisson: two different bulb versions from Brightsstar are running in parallel with same electrical power of 21W installed in the same reflector setup.

24W H3 spot @ 21 W

21W H3 spot @ 21 W

21W H3 bulb

24W H3 bulb

Very small foglights having different HID bulbs inside. The 24W H3 bulb does not fully fits inside the hosuing without some extra work. Basically the extreme compact 21W H3 bulb is the right idea because such a bulb style fits in any type of halogen reflector! The easiest way to get HID lights is to install them in existing H3 reflectors.