HP = Hella High Performance Xenon Blue - Produced under Hella's stringest testing requirements, the High Performance series of bulbs beat all others on the market. Correct filament alignment assures maximum light output and blue glass provides the crisp white beam pattern consumers demand. Sold in pairs. DOT compliant, road legal in all states. Approx. light color 5000K.

XB = Hella Optilux XB Xenon Blue - These bulbs are filled with xenon gas and utilize a blue quartz glass which allows the bulbs to simulate the color of actual daylight. Not DOT compliant, for off-road use only. Approx. light color 6000K

XP = Hella Optilux XP Xenon White - These bulbs are filled with xenon gas for enhanced bulb life and utilize a violet coated glass. DOT approved. Approx. light color 4000K.

XY = Hella Optilux XY Extreme Yellow - Designed to give you better visibility in extreme weather conditions as well as provide the look of GT Series race car lights. Yellow beams provide a better color contrast in rainy, foggy, and white out conditions. Not DOT compliant, for off-road use only. Approx. light color 2500K.