D1 - D1R / D1S HID Bulbs

The biggest design innovation over previous HID bulbs, is that the D1S and D1R bulbs are attached directly to a metal box at the base of the bulb called an igniter.

While there are no noticeable performance advantages over D2 Bulbs, D1S and D1R Bulbs are only disadvantaged by a higher cost of replacement due to the igniter being permanently attached.

In theory, the benefit to attaching the bulb to the ignitor is that this design will allow for a more reliable ignition of the arc-lamp in cold weather where a weak battery may previously have caused spiking and ignition failure.

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