Power with 4.5 ... 5.0V. Can use 3x1.5V batteries, 4x 1.2V NiMH batteries or sell phone charger with 5V output. It works too with 3.7V Li ION battery but brightness is low.
D1A ... D7A and D1B ... D7B are red or yellow LED's. Blue and white will not work at this voltage.
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