In StockSunmaster 400W Metal Halide Lamp
£26.96£29.95Save £2.99
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Description
The Sunmaster 400W Metal Halide Lamp is a powerful vegetative-stage grow light designed to deliver bright, blue-white light for strong, healthy growth. Engineered for HID lighting systems, it promotes compact structure, vigorous leaf development, and solid root establishment—making it ideal for growers seeking professional results during early plant stages.
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400W Output – Provides intense, high-quality light for vegetative growth in medium to large grow spaces.
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Blue-Weighted Spectrum – Encourages strong stem and leaf development while reducing stretching.
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High PAR Output – Produces excellent photosynthetically active radiation for fast, healthy growth.
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Universal E40 Fitting – Compatible with all standard HID reflectors and ballasts rated for 400 W.
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Optimised for Vegetative Stage – Ideal for use before switching to HPS during flowering.
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Long Lamp Life – Delivers consistent performance over multiple cycles with minimal lumen loss.
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Reliable Brand Quality – Manufactured to Sunmaster’s professional lighting standards for consistent results.
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Improves Plant Strength – Balanced spectrum supports dense canopies and resilient structure.
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Easy to Install – Simple screw-fit design allows quick, hassle-free replacement.
The Sunmaster 400W Metal Halide Lamp combines high output, balanced spectrum, and proven reliability—helping indoor growers achieve dense, healthy vegetative growth ready for maximum flowering potential.
Key facts
| Type | Metal halide grow lamp |
|---|---|
| Wattage | 400W |
| Brand | Sunmaster |
| Fitting | E40 screw fit |
| Works with | Standard HID reflectors and ballasts rated for 400W |
| Spectrum | Blue-weighted, for vegetative growth |
| Packs | Single lamp or box of 12 |
| Sizes | Box (12), Single |
| Category | HID Lighting |
How to use
Screw the lamp into an E40 holder in a reflector powered by a 400W ballast. Use it through the vegetative stage, then switch to a sodium (HPS) lamp for flowering.
Let the lamp cool before you take it out. Other lamps are in HID lighting.
Questions
What fitting does it have?
A standard E40 screw fitting, which suits standard HID reflectors.
When should I use a metal halide lamp?
During the vegetative stage. The blue-weighted light builds strong stems and leaves and reduces stretching. Change to a sodium lamp for flowering.




