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 Sep 29 - Oct 4

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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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4.5 ★★★★★
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Susan Cedar
Bozeman, US
★★★★★ 4
My dog loves glowing fetch at night!
Style: Glow Balls (Pack of 3), Size: 2.5 inch
Fantastic. Sturdy. My dog loves them Glow in the dark is great for fetch at night. I keep a flashlight with me because the glow doesn't last really long. But they charge very quickly and are really bright.
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Reviewed in the United States on February 22, 2026
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Maddox
Bozeman, US
★★★★★ 5
Indestructible
Style: Fetch Balls (Pack of 2), Size: 3 inch
These balls are indestructible! We have a lab and a lab mix and they CANNOT damage these balls. They love them for fetch and to just chew on them (slightly squishy, but NO damage). Best toys we have bought for them.
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Reviewed in the United States on April 19, 2026
A
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Animal Lover
Louisville, US
★★★★★ 5
Great trial set. Just be careful throwing the orange one!
Style: Assorted Balls (Pack of 3), Size: 2.5 inch
Blue isn't that easy to see in the yard White charges with bright light/UV and is truly a game changer for night-time fetch. Both dogs clearly favor it. Orange is easy to see in the grass at day They're 3 different weights as well, so double trial. I prefer medium for my big dogs, though light performs well too The orange is HEAVY and unyielding. Do NOT throw it with a ball thrower. It could damage your house or knock your dog out. Seems tough though.
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Reviewed in the United States on January 16, 2026
S
Verified Purchase
Spo509
Dallas, US
★★★★★ 3
Not as good as chuck it anymore
Style: Fetch Balls (Pack of 10), Size: 2.5 inch
I have bought these before and the where just like the chuck it balls. These are not those balls. The are lighter and my dog has already cause damage to one
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Reviewed in the United States on March 16, 2026
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Verified Purchase
Amazon Customer
San Leandro, US
★★★★★ 5
They work! Even if you hate socks
I am not a sock wearer. Can't stand having my foot entirely shrouded in cloth. I don't wear socks with my sandals, slides, clogs and other shoes most of the year. Only on the coldest winter days. I know, It's weird. So, with my sock phobia one thing that happens is your heals get dry and rough. I opted to try these because the toes are free. I barely notice the socks on my heels/ankles when my toes get air (outside of bedcovers always). I put good thick lotion on my heels and sides of feet. A little less on the toes so they don't stain anything. The silicone lining on the heel holds that lotion against the affected areas. In a couple days my feet felt soft and looked pretty. No cracks, no white roughness. They look pink and freshly spa-ed. Fit is good on size 9 feet with thickish ankles. Highly recommend.
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Reviewed in the United States on September 2, 2025

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