not necessairly... I used my lows in the projector lense but i had to do some slight modification to the bulb... i took the O ring off of it and took a cordless dremel and trimmed off the lip that the O ring sits on... when holding the bulb in hand that o ring is now kinda loose, but it won't slip off, once you have the bulb in the socket, it seals up nice and tight. But I just did it to save myself from needing to run out and buy new bulbs/harnesses.One thing you guys should probably know is that you need to convert the low beams to high beams by changing the harness (autozone has these). Low beam bulbs will not go into the casings. It has something to do with the projector and the way it works.