Hello, JLP, here are the optional bulbs for this festoon holder: 12V Clear T3 Festoon LED 2700K 12V Frosted T3 Festoon LED 2700K 24V Clear T3 Festoon LED 2700K 24V Frosted T3 Festoon LED 2700K 12V Clear T3 Festoon LED 3000K 12V Frosted T3 Festoon LED 3000K 12V Clear T3 Festoon LED 4000K 12V Frosted T3 Festoon LED 4000K 24V Clear T3 Festoon LED 3000K 24V Frosted T3 Festoon LED 3000K 24V Clear T3 Festoon LED 4000K 24V Frosted T3 Festoon LED 4000K 5w 12V Clear T3 Festoon Xenon 5w 12V Frosted T3 Festoon Xenon 10w 12V Clear T3 Festoon Xenon 10w 12V Frosted T3 Festoon Xenon 5w 24V Clear T3 Festoon Xenon 5w 24V Frosted T3 Festoon Xenon 10w 24V Clear T3 Festoon Xenon 10w 24V Frosted T3 Festoon Xenon 7w 24V Frosted T3 Festoon Xenon