These very efficient HID elliptical light bulbs give off vast levels of warm white light, with acceptable colour rendering, making them suitable for floodlighting in city centres and residential areas as well as for commercial and industrial applications. Features a ES-E27 Edison screw (27mm) base/cap.This Plus version is more efficient than the standard version producing more lumens per watt. NB: Internal ignitor, however still requires a ballast in the fitting in order for this light bulb to run.