What is a GU10 Light Bulb?
The GU10 is the most common type of spotlight bulb found in most homes today. It is otherwise known as a PAR16 bulb and is often used in places where a bright, directional light is needed, such as kitchens and workspaces. It has the classic spotlight shape, with a narrow base that widens into a flat or slightly rounded aperture.
‘GU10’ refers to the type of fittings these bulbs have. Two short, square-ish pins protrude from the base of the bulb. Like the bayonet cap, this is a ‘push-and-twist’ type of fitting (although a GU10 bulb will not fit in a BC fitting and vice versa).
Halogen GU10 bulbs are commonly made from plastic. Be careful not to confuse a GU10 bulb with an MR16 bulb. The two look almost identical, except for the fittings, which are much smaller, needle-like pins on an MR16 and will not fit a GU10 lamp.
An EU directive that took effect in 2016 has banned halogen GU10 bulbs from sale in the UK. However, there are energy-saving alternatives available.
Energy-saving GU10 spotlights
The CFL (Compact Fluorescent Lamp) lightbulb was the early replacement for high-energy bulbs, but they often don’t look like their halogen counterparts. A CFL bulb is instead a narrow fluorescent tube that is turned into a compact shape (hence its name). In GU10 CFL bulbs, the tube is housed inside the bulb casing, so it still gives off a directional light. The shape of the bulb may differ slightly, but any GU10 fitting should fit existing lamps.
'Long barrel' GU10s are a variation on the typical GU10 spotlight, and are designed for the non-standard light fixtures used by some furniture and home furnishings companies. Long-barrel GU10s are around 75mm in length, compared to 50-55mm for a standard GU10.
LED GU10 lightbulbs have been designed to look like the halogen bulbs they supersede. They have the classic GU10 shape but are most commonly made of plastic to hide the bulb’s componentry. As the technology develops, the bulbs more closely resemble their halogen counterparts, and there are now glass-bodied GU10s available which look almost identical.