These superb LED GLS light bulb consumes only 8W of power yet give a light output comparable to a standard 40W GLS light bulb, reducing electricity costs by almost 80%. Features a ES-E27 Edison screw (27mm) base/cap.Providing a crisp & clean daylight colour they give off virtually no heat and have an amazingly long life of up to 20,000 hours.Please visit the manufacturer\'s website for up-to-date dimmer switch compatibility lists for this Crompton Lamps LED GLS light bulb before purchase.To find the answers to some common questions about LED dimming, please read our guide Dimming for Dummies.Need more help in choosing a suitable light bulb? Read our guide What is a GLS Light Bulb.