I ordered light casings and LED bulbs (that the site recommends). 1st the bulbs did work without switching positive and negative polarities. -But the bulbs that were originally installed of the one that I purchased from the auto-parts store didn't need their polarities reversed, so I suspect a manufacturing defect that the have to be aware of because the rep knew the immediate fix. 2nd they don't fit my truck because the back of the bulb was to wide for the light fixture to fit 3rd they asked me to return the bulb in original condition (I suspect they will re-sale them to someone else) at my own out-of-pocket expense. In summation, they recommended and sold me a defective light bulb that does not fix... User's recommendation: DO NOT USE.