E27 ST64 Filament Bulb 40 W 2700 K Clear Glass — Vintage Edison Shape, 30,000 h, 220–240 V
E27 large screw filament bulb in the classic elongated ST64 Edison shape — clear glass, visible filament, 40 W, 2700 K warm white, rated 30,000 hours, 220–240 V. Suited to exposed-socket pendants, festoon strings, Christmas tree clusters, and any fitting where the bulb silhouette is part of the display.
Technical specifications
| Cap type | E27 — large screw |
| Wattage | 40 W |
| Colour temperature | 2700 K — warm white |
| Bulb shape | ST64 — elongated Edison — visible filament — clear glass |
| Lifetime | 30,000 hours |
| Voltage | 220–240 V AC |
| Dimmable | Check fitting compatibility before installing a dimmer |
ST64 Edison Bulb — elongated silhouette, visible filament, warm 2700 K glow
The ST64 is the elongated, tubular-bodied Edison shape — taller and narrower than a standard globe, with a distinctive shoulder that tapers to the cap. At 64 mm in diameter and approximately 140 mm in height, it has a strong visual presence in exposed-socket fittings, festoon strings, and Christmas tree clusters where the bulb itself is the decorative element. The clear glass allows the filament to read clearly from a distance — in a festoon string or multi-bulb pendant, the filament pattern across several bulbs creates the visual effect. At 2700 K, the output is warm white, close to the tone of a traditional incandescent and flattering to wood, brass, and warm-toned interiors. At 40 W, the output is sufficient for ambient and decorative use; it is not a task light. Confirm the cap type is E27 (large screw) and check the bulb dimensions against your fitting before ordering.
For Christmas tree use, multiple bulbs on the same festoon circuit create a cluster effect — the filaments visible through the branches give a warmer, more considered result than standard fairy lights. For year-round use in exposed pendants or industrial-style wall lights, the ST64 shape suits interiors with a vintage, industrial, or rustic character. At 40 W per bulb, check the total wattage against your festoon cable’s maximum load before ordering multiple bulbs on the same circuit. Browse our fairy & festoon lights collection or read our home lighting ideas guide. Standard delivery is 5–7 working days — free on orders over €50.
Common questions
What is the difference between ST64 and other Edison bulb shapes?
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ST64 refers to the shape code: ST = straight taper, 64 = 64 mm maximum diameter. It is taller and more elongated than a G95 globe (rounder) or a G45 small globe. The ST64 silhouette is the most recognisable vintage Edison shape — the one most associated with festoon strings and exposed-bulb industrial pendants. If your fitting has a narrow socket or limited internal height, check the bulb dimensions (approx. 64 mm × 140 mm) before ordering.
How many bulbs do I need for a Christmas tree?
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For a 6–7 ft tree with an exposed-socket festoon cable, 10–15 bulbs gives a full, even result. For a smaller 4–5 ft tree, 6–8 bulbs is sufficient. Space the sockets evenly through the branches rather than concentrating them at the tips — the filament glow reads better from inside the tree. At 40 W per bulb, check the total wattage against your festoon cable’s maximum load before ordering.
Can I use this bulb outdoors?
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The bulb itself has no IP rating and is not weatherproof on its own. For outdoor festoon strings, the cable and sockets must provide the weatherproofing — confirm they are rated for outdoor use before installing. The bulb must be fully seated in a weatherproof socket to be protected from rain.
Is this bulb dimmable?
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Dimmability depends on the specific LED driver inside the bulb and your dimmer switch type. Check the bulb packaging or product datasheet for dimmable confirmation before pairing with a dimmer. Using a non-dimmable bulb on a dimmer circuit can cause flickering or reduce bulb lifespan.
Will the filament be visible through a frosted or opaque shade?
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No — the decorative filament effect is only visible through a clear or open shade. In a frosted, opaque, or fabric shade, the bulb will function normally but the filament silhouette will not be visible. This bulb is best used in exposed-socket fittings, open pendants, or festoon strings where the bulb is part of the visual display.
Shop the full LED bulbs range or find festoon inspiration in our home lighting ideas guide. Free delivery over €50 — 30-day free returns.