JCB 4W GU10 LED Bulb Non-Dimmable Daylight 6500K - 250lm

The JCB 4W GU10 is a non-dimmable LED spot bulb delivering 250 lumens at a daylight 6500K colour temperature, designed as a direct replacement for 35W halogen GU10s. The two-pin twist-lock GU10 base fits standard UK mains-voltage spotlight fixtures without requiring a transformer, making retrofitting straightforward in kitchens, bathrooms, utility rooms and commercial spaces.

The 6500K daylight colour temperature produces a cool, blue-white light that increases perceived brightness and colour clarity, making it well-suited to task lighting over worktops, vanity mirrors, technical workspaces and areas where accurate colour rendering matters. The 100° beam angle provides wide flood coverage rather than a narrow spotlight effect, distributing light evenly across a broader area from each fitting.

At 4W consumption versus the 35W halogen equivalent, the bulb reduces energy use by approximately 89% per fitting. The 250 lumen output is lower than many current GU10 LEDs (which typically deliver 300-400 lumens at 4-5W), so this bulb suits applications where moderate brightness is adequate or where multiple fittings provide cumulative illumination. JCB rates the bulb for up to 10 years of typical household use, based on an average of 2.7 hours per day.

The bulb carries an Energy Rating of F under the revised 2021 EU energy label scale (which shifted all ratings downward to reserve A for future ultra-efficient technologies). An F rating is standard for LED bulbs in this lumen-per-watt bracket and does not indicate inefficiency relative to halogen predecessors.

Is this bulb dimmable?

No. This JCB GU10 is non-dimmable and must be used with standard on/off switches only. Installing it on a dimmer circuit will cause flickering, buzzing or premature failure.

What does 6500K daylight colour temperature look like?

6500K produces a cool, blue-white light similar to overcast daylight or a cloudy sky. It appears noticeably cooler and bluer than the warm yellow-white of 2700K-3000K bulbs, making it well-suited to clinical, technical and utility spaces but less comfortable in living rooms or bedrooms.

How does 250 lumens compare to other GU10 LEDs?

250 lumens is moderate output for a 4W GU10. Many current GU10 LEDs deliver 300-450 lumens at similar wattages, so this bulb is best used where softer light levels are acceptable or where multiple fittings provide cumulative brightness.

Does the GU10 base fit all mains-voltage spotlights?

Yes. The GU10 two-pin twist-lock base is the UK standard for mains-voltage (230V) spotlight fittings. This bulb does not require a transformer and fits directly into existing GU10 sockets found in most UK downlights, track lights and spotlight bars.