A light safe bulb can be used in any standard ligh bulb outlet. The light can be on at all times while coating your screen and exposing your screen. This will help with visibilty while registering your screens and washing out your screens in the dark room. The light safe bulb can be used with all emulsion without the fear of exposing your screen. The darkroom safe light s equipped with a heavy-duty 130 volt filament, allowing it to last over 2000 hrs.