I have ones I have moded for more than 1 Year now and its a normal 1/4 watt resistor and they dont get to hot. they good for 12 to 14 volts and wont burn out.
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LED's you have to watch because you get lots of differint LED's with tempreture tollerances and Voltage tollerances and if you install ones that cant tollerate the headlight heat they dont last long