The plug-in window candle comes with a solid metal weighted base. It will fit on almost any width windowsill. The bulb is LED, screws in, and has an internal timer (on for 12 hours/off for 12 hours). 12 Hour timer alleviates the need for a dawn/dusk sensor. It illuminates in the same traditional incandescent color as other plugs in candles and remains cool to the touch. The bulb has a long life and is rated to last 10,000 hours.