Solar energy supply, no extra utility electric cost, and no need to replace the battery. Light sensor controls the solar Christmas lights charging at daytime and auto on at dark. 8 Modes&Memory Function: 8 Modes(combination, in wave, sequential, slo glo, chasing/flash, slow fade, twinkle/flash, and steady on). Build in Memory chip save your last modes setting and no need to reset mode every time. .
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