Evan Designs U3W Simulated Model LED Welding Kit, by 3mm LED's, Great for a welding scene made up of 1 solid blue & 2 random flashing white The electrical componets allow you to use AC/DC/DCC, 7-19volts, completely assembled You can use a 9v battery, track power, 12v adapter to light our LEDs each set comes with a resistor, capacitor & rectifier, thus no polarity issues A 12 volt 2 amp adapter (PDC12) will run 100 LEDs