SKU: 35237980179
400 watt grow light bulb

400 watt grow light bulb Mass Metal Halide 400 Watt Bulb – MASS Hydroponics

Sale price$22.01 Regular price$24.46
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Ships within 48 hours · Estimated delivery Jul 11 - Jul 16

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Description

400 watt grow light bulb Mass Metal Halide 400 Watt Bulb – MASS HydroponicsMass Metal HalideBring the spectrum of the sun indoors! Mass Metal Halide is your full spectrum light source for highest quality flowering (and full growth cycle) indoors! One of the most powerful MH bulbs ever, with brighter output and a superior light spectrum. Designed to bring out the best in your plants during the flower cycle, increasing quality and even yield in many varieties! Its a myth that you need HPS for flower, and our MH bulb will show

Mass Metal Halide

Bring the spectrum of the sun indoors!

Mass Metal Halide is your full spectrum light source for highest quality flowering (and full growth cycle) indoors! One of the most powerful MH bulbs ever, with brighter output and a superior light spectrum. Designed to bring out the best in your plants during the flower cycle, increasing quality and even yield in many varieties! It’s a myth that you need HPS for flower, and our MH bulb will show you! Our bright white light is very similar to natural sunlight and has been shown to produce cannabinoids and terpenes that other indoor light sources don’t produce. Many growers notice huge improvements compared to LEDs, We have much better full range UV and IR, and a great color balance of efficient visible light. It’s easier to keep plants healthy with our light spectrum under a wider range of temperatures, so you can relax and enjoy your garden. The quality of flowers produced under Metal Halide is so incredible that I wanted to keep this technology going and try to deliver the best bulb possible!

For flowering, a 400w can cover up to a 3x3, 600w can cover up to 4x4 and a 1000w can cover up to a 5x5. For vegging, they can cover even larger areas.

To use our light, you’ll need a ballast and a hood/reflector. The ballast wattage must be matched to your bulb wattage, do NOT dim a metal halide bulb, even if your ballast has a dimming option. Please purchase the appropriate wattage for your space. We recommend the use of a PAR meter to get the exact proper light levels throughout your garden, as each reflector spreads light differently. The use of a PAR Meter is essential for large yields under MH. A rough estimate is 14-18 inches away from 600w and 24-30 inches away from 1000w. With air cooled hoods you can also get even closer! Our bulb is Enclosed Rated, so we recommend the iPower air cooled or cool tube hoods which can be connected directly to your exhaust duct. We recommend the Quantum ballast, which is available in both 600 and 1000 watts.

Please follow all safety precautions on the box and on our website. Our bulb is very safe when used properly! When installing, wear a clean glove: do not touch the bulb with your fingers, wipe clean with dry cloth if you do! Avoid spraying any liquids near the bulb. Oils from your fingers or liquids from sprays can heat up and explode the glass, so keep it clean. Enclosed hoods provide additional protection.

We have a website full of information to help you understand our light on a deeper level, and get the best out of your grow on your very first round! Take some time to read our site, and have a great grow! www.massmetalhalide.com

To see which equipment to use with your bulb, visit massmetalhalide.com/equipment to learn about hoods, ballasts, and compatability

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 35237980179

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Greg Sanders
Chelsea, US
★★★★★ 1
Cheap/flimsy/garbage
Color: Grey
Garbage product! Flimsy! Cheap! Useless. If I could give it negative stars I would
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Reviewed in the United States on May 10, 2026
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Stephen Sauro
Natrona Heights, US
★★★★★ 5
Know what you're doing before you order
Color: Grey
There's a very high quality item easy to assemble last a long time it was pretty nice. For the first one. My roommate talked me into buying the second one and then he backed out of the deal he didn't have the money. So I returned it at the Amazon store and like a boomerang it came back. I end up having to buy it anyway you're still sitting in the box
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Reviewed in the United States on March 2, 2026
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DrCMackey
Pawtucket, US
★★★★★ 4
Must have for at home workers!
I bought this divider because I work from home and wanted to have a professional and neutral background for video conferencing. There were other dividers that I contemplated purchasing because of the variety of colors but ultimately decided to go with this divider because of prime shipping. I noticed in the reviews of other dividers on Amazon a lot of people talked about cracks. I noticed a few cracks on mine but they are small and minimal in appearance so it does not bother me (see pictures). Overall, it came in great shape. I love the color of the divider. I was concerned it would come solid brown based on the pictures but it is more rustic, which I love. The dividers are tall and long so it covers a great amount of space. The hinges go either way which is also a plus. I will say it seems slightly unstable on carpet but it would only move if bumped into so that is not much of a concern. Most likely would be more sturdy on solid/ hardwood floors. Overall, I am super happy with my purchase. Definitely worth the price with fast 2 day prime shipping and no assembly needed.
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Reviewed in the United States on April 4, 2021
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Sulma Bejarano
Fort Morgan, US
★★★★★ 5
Pere portátil
Color: Grey
Perfecto para cubrir camas en la sala
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Reviewed in the United States on April 3, 2026
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Amazon Customer
Phoenix, US
★★★★★ 5
Good Product
Size: 3 Panel-102'', Color: Beige
I got these dividers for outdoor use for some privacy from neighbors. They arrived quickly and were easy to set up. They look good, and though the legs don’t offer stability against any amount of wind—which I expected as it wasn’t advertised for outdoor use—all it took was placing a cinder block on the feet to hold it up right. Coverage is good, it’s easy to fold and move as needed, and it’s light weight. All in all a decent product. I will caution the purchase of “used like-new,” as both of the dividers I ordered were previously returned items, and one came missing a cap, instructions were not included, and the poles were all mixed up and not properly labeled. If I had not ordered a second divider (which did include the instructions) I would have had a much harder time figuring out which pieces were which and how to put them together.
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