Using an automatic timer eliminates the need for you to manually turn lights on or off. The Outdoor Digital Dusk-to-Dawn Programmable Plug-In Timer with Photocell takes care of this process, offering a more convenient and secure home environment while promoting energy conservation. It has a weather-resistant casing so it can be mounted in an indoor or outdoor setting and can be used with almost any two and three pronged plug-in light setup. The timer will be activated when the built-in photocell senses that the ambient light level is at darkness. Use it for a few indoor and outdoor lights to keep you from coming home to a dark house or to give your home that lived in appearance to help deter criminals. If you are someone who simply forgets to turn off the lights at night, let the timer do the work. You can also program the timer to be active for specific hours during the evening; easily done with the aid of only two buttons and a digital LCD screen that also displays as a clock. An LED light even indicates when the timer is on. By limiting the amount of time your lights are on after dark you can significantly reduce the amount of energy being used as well as the associated costs.# Outdoor Digital Dusk-to-Dawn Programmable Plug-In Timer with Photocell # Owner's manual .Operational Modes # Continuously on from dusk to dawn # On at night limited by a program # Manually switched on This device is designed to reduce the amount of time lights are used after dark. If you program the timer to turn on from 6pm to 12pm, but if the sun does not set (or it is not in darkness) until 7pm, the timer will not go on until 7pm. If needed, you can manually turn the timer on in the day or lighted conditions, however it will remain on until dawn the next day, it encounters the programmed off timer, or you manually turn it off.