1.The USB plug allows you to use multiple power source. 2.The window light can plug in any usb-based charger unit, so you can easily power them anywhere. 3.the curtain fairy lights is safe to touch.Never get overheat touch after long time of usage. 4.which is perfect for indoor/outdoor patio decorations, doors, floors, ceilings, bedroom, livingroom, around , Christmas, , Valentine's Day, Holidays, outdoor wedding, backdrop, shopping center etc. Length: 1 meters Width: 3 meters Quantity: 100 lights Battery box: Not included 3xAA batteries 10 lights per meter, hanging down by 10 is equivalent to 100 lights Colour:As Shown Material:pvc Type: A: Positive white light Package Contents: 1x string light 1x battery box 1x USB cable 1x Chinese and English manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.