GU10 LED Spotlight Bulb 4W 450lm Dimmable - Daylight 6500K

This Energizer GU10 spotlight bulb draws 4W and puts out 450 lumens at 6500K, which is the coolest, brightest white in the domestic range and reads as clean daylight rather than the yellow of a traditional halogen. The beam is a wide one, so the light spreads out across a surface instead of pooling in a tight circle under each fitting. The pack gives it as a 40W replacement, and the printed lifespan is 15 years, or 15,000 hours. It is a dimmable lamp, which is worth knowing, because a good many GU10 LEDs are not.

GU10 is the twist-and-lock cap found in most mains-voltage downlights, track heads and spotlight bars, so if your old bulb has two small pins on a flat base and turns a quarter turn to release, this is the right fitting. The 6500K colour is a deliberate choice rather than a default. It renders whites as white and keeps detail sharp, which suits a kitchen worktop, a workbench, a garage, a utility room, a home office or a display shelf. In a sitting room or a bedroom it will feel bright and clinical next to warm white lamps, so we would keep the two apart rather than mix them in one ceiling.

For dimming, pair it with a dimmer made for LED loads, usually a trailing edge type, and check the dimmer's minimum load: one 4W lamp on a switch rated from 40W upwards will often flicker, while four or five together behave. The energy rating is E. Each unit is a single bulb, and the minimum order is 12, sold in multiples of 12, which is a sensible way to do a whole ceiling at once and hold a spare back. Our wider Energizer LED range includes other GU10 bulbs, among them a 3.6W warm white 3000K version.

Will this fit my existing GU10 downlights?

Yes, if the old bulb has two stubby pins on a flat base and twists a quarter turn to come out. GU10 runs on mains voltage with no transformer, so it is not interchangeable with 12V MR16 or GU5.3 lamps.

What does 6500K daylight actually look like in the room?

It is a crisp blue-white with no yellow in it, the coolest of the common domestic colour temperatures. Colours and printed detail stay sharp under it, which is why it is chosen for worktops, workbenches and task areas.

Which dimmer switch should I use with it?

Use a dimmer built for LED loads, commonly a trailing edge model, and check its minimum load figure. A single 4W lamp often falls below the minimum on an older dimmer and will flicker or fail to strike.

Does the manufacturer state an IP rating?

No IP figure is given in the specification and none is printed on the retail pack, so we state none. Treat it as an ordinary indoor lamp for a dry, enclosed setting.

How long is it meant to last?

The pack states a 15 year lifespan, given elsewhere on the same pack as 15,000 hours. That figure assumes typical household use of roughly three hours a day rather than constant running.

How many bulbs do I receive?

One bulb per unit. The minimum order is 12 units, sold in multiples of 12, so the smallest quantity you can buy is 12 separate single bulbs.