E27 (ES) LED GLS Bulb 4.2W 470lm Dimmable - Cool White 4000K

This is a standard GLS bulb, the familiar rounded pear shape that most table lamps, pendants and ceiling fittings in a British home were built around. It draws 4.2W and gives 470 lumens of LED light, and the retail pack states that it replaces a 40W filament bulb. The cap is E27, the larger of the two screw fittings and often written as ES on a fitting or an old bulb box. Colour temperature is 4000K, a cool white that sits between the yellow cast of a traditional bulb and the blue tone of daylight.

Cool white suits the parts of a house where something is being done rather than unwound in: kitchen ceilings, utility rooms, home offices, garages, workshops, hallways and stair landings. It keeps whites looking white and makes edges and print easy to read, where a warmer bulb would put a yellow wash over everything. It is worth keeping one room consistent, because 4000K beside a 2700K warm white lamp looks noticeably cooler. The pack quotes the 470 lumens in a sphere, meaning the figure is measured all the way round the bulb rather than in one direction, which is what you want under a shade, in a pendant or inside a diffused ceiling fitting.

The bulb is dimmable, so it can go on a dimmer circuit, but the dimmer needs to be one rated for LED loads; an older dimmer sized for 40W filament bulbs often has a minimum load well above 4.2W and will flicker or buzz at the low end. The energy rating is class E and the pack prints a 15 year lifespan. Each box holds a single bulb, with a minimum order of 12 in multiples of 12. Our wider range of LED bulbs also covers B15 (SBC) candle bulbs and GU10 lamps in warm white 2700K and cool white 4000K.

How do I know if my lamp takes an E27 bulb?

Take the old bulb out and look at the base. An E27 has a spiral screw thread roughly 27mm across, which is the larger of the two common screw sizes; the smaller one is E14.

Will it work on a dimmer switch?

Yes, the specification lists it as dimmable, but the switch itself must be a dimmer made for LED loads. Older dimmers built for filament bulbs often have a minimum load far higher than 4.2W and can flicker.

Is 470 lumens bright enough to replace my old 40W bulb?

The pack states this bulb as a 40W replacement, so in a table lamp, a bedside light or a small pendant it should read as the same brightness.

What does 4000K cool white actually look like?

It is a clean, neutral white with no yellow in it and no strong blue either. Next to a 2700K warm white bulb it will look distinctly crisper, so try to keep one room to a single figure.

Is an IP rating given for this bulb?

No. Neither the specification nor the retail pack prints an IP rating, so we do not state one for it and make no protection claim on its behalf.

How many bulbs do I receive?

One bulb per box. The listing has a minimum order of 12 boxes, sold in multiples of 12, so an order of 12 brings you 12 individual bulbs.