These 100 x led lights are powered by batteries the benefit being they still work in winter or in areas which get no natural light in the day they have a simple to operate timer 6 hours on18hours off once youve pressed the button the lights will operate 6 on 18 off all the time so that you dont have to remember to turn them on and off these lights are suitable for indoor or outdoor use and are the perfect alternative to solar or mains power lightingr 99m of illumination30cm from batte