These string lights are charged using solar power & will turn on at dusk & off at dawn automatically. They are easy to install with no electricity required & come with 50 white colour LED’S, 2 switch modes of solid & flashing. They are perfect for decorating trees, shrubs, garden decking or even outdoor Christmas trees.. Approx Total Length: 6.9m/17.5’. They require 1 x AAA Ni-MH rechargeable battery (included).