This Crompton Lamps 5.5W fully dimmable LED golfball light bulb with a BC-B22d bayonet (22mm) cap is a retrofit replacement for a incandescent 40W light bulb, but has the potential to reduce your home lighting bills & reduce the frequency of needing to replace your light bulbs.LED technology has superior energy efficiency than traditional incandescent or halogen light bulbs which helps you save on your energy bills & helps the environment too. Whereas a traditional light bulb would use 40W to produce 470lm, this LED version uses just 5.5W equating to an excellent energy-efficiency of 85lm/W. This high-performance LED light bulb sports a thermal plastic body that is specifically designed to dissipate heat effectively. This reduces the light bulb's running temperature & places less strain on its components resulting in a longer life span. With a long life of 25, 000-hours, this LED golfball light bulb boasts an incredible 13.7-year lifespan if used for 5-hours a day. These light bulbs dont need to be replaced as often which results in less money spent on replacement bulbs, less time spent replacing them, & less old light bulbs going to landfill too. Combine this superior longevity, negligible maintenance & replacement costs with the LED light bulbs notable energy efficiency; then the savings from each light bulb has the potential to reduce your lighting costs by up to 86%. This dimmable LED light bulb features Duo Dim™ Technology making it compatible with most leading & trailing edge dimmers. Cool white (4000K) bulbs produce a cooler, crisp light & are well suited to more stimulating environments. This makes them great in kitchens, workplaces & is also excellent for bathrooms as there is no colour cast; so applying makeup is much easier. Unlike older other energy-saving technologies, LED bulbs light up instantly, with no waiting time to warm up to full brightness. This LED golfball light bulb is a small round light bulb that will retrofit directly to any existing BC-B22d fixture; whether that be smaller domestic light fittings such as bedside lamps or fixtures with limited space or up to large-scale commercial installations.