LED bulbs

LEDs are voltage and amperage rated. you are suppoosed to run them in series to devide the 12V into manageable xV chunks, ie 3 5V in series to operate off a 12v source. They make 12V also but more common is the cheap 2.1V 15mA they need resistors to live! use this calculator...
http://led.linear1.org/led.wiz

for instance 5 in series with a 220ohm resistor, in 8 parallel banks would equal 40 LED array that will survive/
13.5V
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