When looking at D2 xenon HID bulbs, it can be tricky to determine which bulb you need. A frequently asked question in our Sales Office is, ‘do I need a D2S, D2C, or D2R?’…
The difference between D2S and D2R is that D2S HID bulbs are designed to be used in a projector headlight application, and a D2R type is made for a reflector application – such as in worklights and some driving lights. You can easily identify them as the D2R has a painted shield onto the glass, whereas the D2S doesn’t.
The D2R HID bulbs have a painted section on the glass because otherwise there would be too much glare in a reflector housing, it acts as a type of deflector to only let the HID light shine in some directions, it also helps to reduce the amount of yellow light that is seen in the light output.
When fitting them, some bases have notches cut in certain places to prevent the wrong type of bulb being installed in the wrong place.
In case you were wondering, HID stands for High-intensity Discharge, based on the type of technology that produces this brilliant light output.