I was skeptical on these, but I have had very good performance out of Niilight products. I have an 04 Ford F350 and they fit perfectly. Advice: Take the collar off the light (twist lock) and put that in the housing 1st, 2nd put on locking ring, 3rd put bulb in and twist lock into collar. The sleeve on the light is removeable via 2 small screws and will rotate 180 degrees to help get pattern correct (better if it was 90 degree increments) but I found that the way they came worked perfect and beam was bright on both low and high beam. First LED to have a stellar high beam pattern and throw. Very impressed. Will update if longevity isn't there like they claim, but so far 2 thumbs way up!!