This Crompton Lamps 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 and 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 and helps the environment too.Whereas a traditional light bulb would use 40W to produce 470lm, this LED version uses just 5W equating to an excellent energy-efficiency of 94lm/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 and places less strain on its components resulting in a longer life span.With a long life of 15,000-hours, this LED golfball light bulb boasts an incredible 8.2-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, and less old light bulbs going to landfill too.Combine this superior longevity, negligible maintenance and 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 88%.This dimmable LED light bulb features DuoDim™ Technology making it compatible with most leading and trailing edge dimmers.Cool white (4000K) bulbs produce a cooler, crisp light and are well suited to more stimulating environments. This makes them great in kitchens, workplaces and 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.