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GrowBright 400 Watt Metal Halide Conversion Bulb
GrowBright 400 Watt Metal Halide Conversion Bulb
In Stock!

This is an MH bulb, designed for use with 400 watt HPS (sodium) or digital ballast systems.

High Output = 38,000 LUMENS!

Similar bulbs sell for $89.95 in hydroponic stores on sale here for...

...ONLY $34.95!

The perfect bulb for VEGETATIVE PLANT GROWTH

Make your 400w HPS system into a "switchable" HPS/MH system with this light bulb!

This is a premium high output Metal Halide Conversion bulb for sale and an unbelievably low price. This 400 watt High Output MH Conversion bulb emits 38,000 lumens - standard 400w MH bulbs which emit only 36,000 lumens. Perfect for 400 watt HPS grow light systems This bulb gives you a higher light output which equates into faster / more plant growth and ultimately higher plant yields.

Fits all standard 400 watt HPS systems.

Spec: S51 type lamp, Mogul based


About the bulb:

  • Works with all 400 watt HPS Grow Light Systems!
  • High Output Delivers Superior Performance
  • Designed Specifically for PLANT GROWTH
  • Brighter than Standard MH lamps
  • Bright White Light Spectrum perfect for Lush, Compact Vegetative Plant Growth!

Common Questions:

Can I use this bulb in the light system I have now?

This bulb is a 400 watt METAL HALIDE CONVERSION bulb and can only be used with systems that have a 400 watt HIGH PRESSURE SODIUM (HPS) ballast. All you have to do is SIMPLY SCREW THE BULB INTO YOUR 400w HPS SYSTEM! No switches, no special ballasts - simply screw the bulb into your existing systems mogul based socket. Note: You cannot use this bulb with any other wattage High Pressure Sodium system (250 watt, 600 watt, 1,000 watt etc) nor can it be used with any other type of H.I.D. lighting ballasts (Metal Halide, Mercury Vapor). This bulb is for use with only the 400 watt High Pressure Sodium type or digital ballast.

Why do I need a specialty Metal Halide (MH) Conversion bulb?

Do you want to grow the best plants possible? You should make the most of your 400w HPS grow light system by using this bulb. Growing plants vegetatively under an HPS bulb makes them stretch and become leggy. When you use this Metal Halide Conversion bulb your plants will grow bushier, greener and better than you could with a High Pressure Sodium bulb. Then when it's time to flower/bloom/bud your plants, simply screw the 400w HPS bulb in for excellent result in that stage of plant growth.

How long does this MH Conversion light bulb last?

These 400w Metal Halide Conversion bulbs have a rated life of 20,000 hours. One year is 8,760 hours. It is, however, suggested that people using Metal Halide (MH) bulbs for growing plants should replace their bulb after about 12 months of use. This ensures your bulb is emitting the maximum amount of light it can before the lamp begins to degrade and emit less light.

Does this bulb come with a warranty?

YES, this GrowBright 400 watt Metal Halide Conversion bulb comes with a 1 YEAR WARRANTY. We stand behind our products 100% and will replace your bulb if it burns out within one year of the purchase date. You can count on us to be there for you during and after the sale. We work hard to keep all our customers happy, please check out our thousands of +feedback responses and you'll see why we are the best!

  • Brand : GrowBright
  • Wattage : 400w
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