B15 LED Filament Candle Bulb 5W 550lm Dimmable - Cool White 4000K

A candle bulb on a B15 small bayonet cap, the narrower of the two bayonet fittings, with two side pins on a cap about 15mm across. The glass is clear, so the four upright LED filament strips inside are on show rather than hidden behind a diffuser. It draws 5W and gives 550 lumens, and the retail pack rates it as a 40W replacement with a 15 year lifespan. Colour temperature is 4000K, which the pack calls cool white: a clean, slightly blue-leaning light rather than the yellow cast of a traditional candle lamp.

B15 is common on chandeliers, candelabra, wall lights and small pendant clusters, so check the old bulb before ordering: if its cap has two pins and measures about 15mm, this replaces it; if the pins sit on a 22mm cap, you need B22, and a screw cap needs E14 or E27. Clear glass suits open fittings and shadeless arms where the filaments are part of the look, and it works equally well under a small shade. Cool white at 4000K sits comfortably in a kitchen, a hallway or a home office, where crisp light helps you see what you are doing.

The pack marks the bulb as dimmable, so it will work on a dimmer, though the dimmer itself needs to be LED-rated; older resistive dimmers built for filament lamps often have a minimum load of 40W or more, which five watts cannot meet, and the result is flicker or a narrow dimming range. The pack carries energy class E. Each box holds one bulb, and the minimum order is 12, sold in multiples of 12, which suits a multi-arm fitting where changing every lamp at once keeps the light even. We also list B15 candle bulbs at 4.2W in both cool white 4000K and warm white 2700K, and at 7.3W in warm white 2700K.

How do I know my fitting takes B15 and not B22?

Pull the old bulb and measure the metal cap. Two pins on a cap about 15mm across is B15, small bayonet; two pins on a 22mm cap is B22, the standard size.

Is 550 lumens bright enough to replace a 40W candle bulb?

Yes. The pack rates it as a 40W replacement, and 550 lumens is a little above what a typical 40W incandescent candle gave, so the room will not look dimmer.

Will it dim properly on my existing dimmer switch?

The pack states it is dimmable, but the switch matters. Use an LED-rated trailing edge dimmer with a low minimum load; old dimmers built for filament lamps often need 40W or more.

What does 4000K cool white actually look like?

It is a neutral white with a slight blue lean, closer to daylight than to candlelight. If you want the warm yellow of an old filament lamp, choose a 2700K version instead.

Does the manufacturer state an IP rating?

No IP figure is printed on the pack or given in the specification, so treat it as an ordinary indoor bulb for dry, enclosed or open fittings in normal living spaces.

How many bulbs do I receive?

One bulb per box. The minimum order on this listing is 12 boxes, sold in multiples of 12, which suits multi-arm fittings and spares kept on the shelf.