FireLight Infrared Bulb

Sale price $204 Regular price $240

Born from over a decade of research and development, the FireLight® Bulb is the heartbeat of everything we offer. It delivers optimized red and infrared light—concentrated in the near-infrared range and extending into mid and far—for unmatched light and heat therapy. With no flicker, and no blue light, this hand-blown bulb supports detox, circulation, cellular repair, and calm. Elemental light, biologically tuned for deep transformation.

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SaunaSpace FireLight Infrared Therapy Bulb - Close Up

FireLight Infrared Bulb

Sale price $204 Regular price $240
Order Processing: 1-3 business days
Sale price $204 Regular price $240

Specifications

General Specifications

Bulb type: R40 

Socket type: E26

Base type: screw-in

Glass color: dark red

Coating/finish: none

Filament: C-9

Filament operating temperature: 2400K

Rated life: 5,000 hours

Product technology: incandescent

Glass processing: tempered, annealed

Glass production method: stained and blown

Dimensions

Bulb diameter: 4.9 in (125 mm)

Stem diameter: 1.7 in (42 mm)

Bulb height: 6.6 in (168 mm)

Materials

Bulb material: hard glass

Cap-base material: brass

Electrical Info

Wattage: 250 W

Input voltage and frequency: 120V at 50–60 Hz1, 240 V at 50–60Hz2

1120V is used in USA, Canada, Mexico, Japan and other select countries.

2240V is used in Europe, Asia, South America, and Australia/New Zealand, and most of the rest of the world.

No One Does Infrared Like Us

We've spent years crafting the perfect hand-blown sauna bulb. We mimic the best of the sun—with none of the harmful UV—to create full-spectrum infrared therapy that is truly one of a kind.

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Silhouette of woman walking toward red spotlight background in dimly lit room
Close-up of Hearth Infrared Sauna Panel with lights on
Silhouette of woman with red light on eyes against background of violet light.
Woman using SaunaSpace Exfoliating Brush on her thigh under red light, inside FireLight Infrared Sauna
Man ballet dancing with and holding woman in dimly lit room with red light cast upon them

293 Reviews from Happy Customers

4.9
Rated 4.9 out of 5 stars
Based on 293 reviews
Total 5 star reviews: 275 Total 4 star reviews: 11 Total 3 star reviews: 3 Total 2 star reviews: 2 Total 1 star reviews: 2
98%would recommend this product
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293 reviews
  • AK Profile picture for Andrea K.
    Andrea K.
    Verified Buyer
    I recommend this product
    Benefits I Notice Pain Reduction, Less Inflammation, Reduced Screen/Technology Fatigue, Radiant Skin, Detox
    My Favorite Features Nature’s FireLight Spectrum Indoors, Convenience of Sauna at Home, Combining Light & Heat Therapy, Portability, Grounding
    Age 40-49
    Rated 5 out of 5 stars
    1 year ago
    Significant reduction in inflammation!

    My father has recently been diagnosed with a rare genetic mutation called Vexas, which causes severe inflammation of the cartilage throughout the body, particularly in the nose and ears.

    After only 10 minutes of exposure to the sauna space infrared bulb, there was a significant reduction in inflammation. Regular use has also been helping to reduce the pain and redness.

    I also have a sauna space bulb and look forward to using it daily to ease aches and pains, rejuvenate my skin, reduce screen fatigue, and simply enjoy basking under the glow.

    QualityRated 2.0 on a scale of minus 2 to 2
    Ease of SetupRated 2.0 on a scale of minus 2 to 2
    I Use ItRated 2.0 on a scale of minus 2 to 2
    ExpectationsRated 2.0 on a scale of minus 2 to 2
  • GB
    Gina B.
    Flag of United States
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    2 years ago
    Bulb & Bodacious

    I've had my Sauna Space for about 2 years now and love it and use it every day. The bulb lasted a long time and I replaced it for the first time recently. Came quickly, beautifully packed and super easy to install. I'm so happy I bought this product and would like one day to make the investment in a larger system. I've recommended it to others. Feels so good! Thank you for this really nice company that makes lovely products.

  • JS
    Jeff S.
    Verified Buyer
    I recommend this product
    Benefits I Notice Pain Reduction, Improved Mental Health/Mood, Immune Support, Less Inflammation, Stress Reduction
    My Favorite Features Comfortable Air Temperature, USA-Handcrafted Quality, Combining Light & Heat Therapy, Convenience of Sauna at Home, Nature’s FireLight Spectrum Indoors
    Age 60-69
    Rated 5 out of 5 stars
    3 months ago
    Red light therapy room

    I actually took one of my walk-in closets and converted it into a red light therapy room made out of red cedar with a 2 inch thick raw edge piece of maple w/ 4 of your infrared bulbs .. I love it! I’ve been using it every day, in the morning for the last three months since completion.

    QualityRated 2.0 on a scale of minus 2 to 2
    Ease of SetupRated 1.0 on a scale of minus 2 to 2
    I Use ItRated 2.0 on a scale of minus 2 to 2
    ExpectationsRated 1.0 on a scale of minus 2 to 2
  • E
    Elise
    Verified Buyer
    Rated 3 out of 5 stars
    6 months ago
    Not the same as their older “Thermalight”

    I ordered this without reading the fine print, just assuming it was the same as the prior bulb that I had purchased from them because the price was about the same. I loved the prior bulb, which was a very deep red handblown glass. Honestly, I felt like the price was worth it for that bulb, but I’m not certain that it’s worth it for this one. It seems similar to other others I’ve seen on the market for less. It still seemed like a good bulb, but less than a month after buying it, I knocked the lamp over and the filament is now broken (my fault) so I need to replace and I’m looking elsewhere.

    QualityRated 0.0 on a scale of minus 2 to 2
    Ease of SetupRated 0.0 on a scale of minus 2 to 2
    I Use ItRated 0.0 on a scale of minus 2 to 2
    ExpectationsRated -1.0 on a scale of minus 2 to 2
    SaunaSpace
    5 months ago

    Thank you for your honest feedback. We’re sorry to hear that the new bulb didn’t meet your expectations, and we appreciate the opportunity to clarify a few things regarding the changes.

    As you mentioned, we switched to a new bulb design—the FireLight® Bulb—in November 2023. While it may look different from the previous ThermaLight Bulb, we assure you that it offers an enhanced experience. The new design uses a slightly lighter red hard quartz glass, which allows more irradiance to pass through, providing a more powerful light and heat therapy.

    Our FireLight® Infrared Bulb delivers 2x the irradiance in the light therapy (photobiomodulation) band of red and near-infrared light (600nm - 1000nm) and also provides more heating. This makes the bulb not only more effective for light therapy but also offers a stronger therapeutic experience.

    Thanks again for sharing your thoughts with us, and we hope you'll consider giving the FireLight® bulb another chance!

  • KC
    kathleen c.
    Verified Buyer
    I recommend this product
    Age 50-59
    Rated 5 out of 5 stars
    9 months ago
    first purchase

    i cannot afford a whole set-up right now, so i purchased a single bulb. i am enjoying it ( i believe i have seen an improvement in inflammation), so are my senior pups!

    QualityRated 2.0 on a scale of minus 2 to 2
    Ease of SetupRated 2.0 on a scale of minus 2 to 2
    I Use ItRated 0.0 on a scale of minus 2 to 2
    ExpectationsRated 0.0 on a scale of minus 2 to 2

The FireLight® Bulb FAQ

The FireLight® Infrared Bulb is the core of our infrared sauna experience—engineered to emit a powerful blend of red, near-infrared, and thermal light. This unique full-spectrum output supports deep tissue warmth, cellular regeneration, and natural detoxification. Below, we’ve answered the most frequently asked questions to help you better understand how FireLight® works, how to use it safely, and what makes it so essential to your healing journey.

What makes the FireLight® Bulb different from other infrared therapy bulbs?

Everything. The FireLight® Bulb is the heart of every product we make, and it’s not just any incandescent.

It’s a near infrared therapy bulb engineered for both photobiomodulation and radiant heat therapy. Its finely tuned tungsten filament runs at a higher Kelvin than standard heat lamps, producing high-output red and near-infrared wavelengths (600–1000nm), ideal for cellular repair, muscle recovery, detox, and mitochondrial rejuvenation.

The bulb is made from hard quartz glass, not soft glass. It’s red-stained, not coated, so there are no chemicals, dyes, silicone, or Teflon. Just clean, pure, high-output light.

Each bulb is splash-tested while operating (yes, literally sprayed with cold water while hot), and tested again at our Missouri factory before it ships.

How hot does the FireLight® Bulb get during use?

Plenty, by design. This 250W bulb has a filament temperature around 2400K, with surface temperatures reaching 300ºF (150ºC). It delivers deep, radiant heat fast, perfect for sauna therapy or targeted red light sessions.

Glow and Hearth include protective guards for safety. Just avoid touching the glass when hot.

Can I stare at the FireLight® Bulb with my eyes open?

We don’t recommend looking directly at the filament inside the bulb. It’s bright, and not meant for eye-level focus.

That said, many users keep their eyes open while reading or working near the light (especially with the Glow or Hearth). Others close their eyes or glance away. The benefits still happen; photobiomodulation doesn’t require eye contact.

Do what feels right for your body—and never force direct eye contact if it feels uncomfortable.

Can I use the FireLight® Bulb in a regular lamp or DIY panel?

We don’t recommend it.

The FireLight® Bulb runs at 250 watts and gets very hot: hot enough to require a properly shielded, grounded, and ventilated fixture. Most regular fixtures simply aren’t built for this power level. Without the right materials and safety features, you risk burns, EMF exposure, or even fire.

Our handcrafted fixtures, Glow and Hearth Sauna Panel used in our FireLight® Sauna, use ceramic sockets, grounded stainless guards, and EMF-safe designs, developed over years of R&D. For safe, low-EMF near infrared therapy, pair your bulb with its proper SaunaSpace home.

How do I know if my FireLight® Bulb needs to be replaced?

It’s simple. If the bulb turns on, you’re getting full power. Unlike LEDs, it won’t slowly dim or degrade. When it’s time, the bulb will just stop working—no guesswork, no decline.

How long does the FireLight® Bulb last, and what happens when it burns out?

Each bulb is rated for 5,000 hours, typically lasting 5 to 10 years based on use. It shines at full strength until the moment it stops—no dimming, just a clean burnout.

If your bulb came with a SaunaSpace product, it’s covered by our five-year warranty. After that, customers receive an exclusive replacement price of $95.

If purchased alone, it’s still covered under standard use: five years for SaunaSpace use, one year otherwise.

Does the FireLight® Bulb emit EMFs?

Like all incandescents, the FireLight® Bulb emits a mild electric field.

To minimize exposure, we strongly recommend using it in one of our EMF-shielded fixtures, Glow, Hearth, or FireLight® Sauna, all of which feature a grounded Faraday stainless-steel guard.

This setup blocks electric fields at the source, delivering powerful red and near infrared therapy with low EMF output.

Can I use this bulb for red light therapy without a sauna?

Absolutely. The Glow and Hearth are perfect for standalone red light therapy, ideal for desks, bedsides, or home wellness zones.

You’ll get the full photobiomodulation benefits, with gentle warmth but without intense sweating.

 Is the FireLight® Bulb full-spectrum?

Yes. Unlike most LED panels, which narrow their output, the FireLight® Bulb offers a broad spectrum of red and near-infrared wavelengths. It’s ideal for whole-body rejuvenation, detox, and mitochondrial support.

Can I touch the FireLight® Bulb with my hands?

Try not to. The red-stained hard quartz glass is more durable than soft glass, but oils from your skin can create hot spots on the bulb over time. If you accidentally touch it, wipe it down with a clean microfiber cloth and a little rubbing alcohol before using.

What happens if water hits the FireLight® Bulb?

Each bulb is splash-tested while hot to reveal microscopic flaws. It’s built to withstand brief, accidental splashes—but not designed for steam or wet rooms. Avoid moisture exposure during use.

Can I use a dimmer with the FireLight® Bulb?

Yes, but we don’t recommend it. The FireLight® Bulb is designed to run at full power for optimal therapeutic output. Using a dimmer can affect the spectrum, reduce the therapeutic effect.

For gentler sauna sessions, just turn 1 or more switches off so you are using less bulbs. When using the Glow and Hearth outside the sauna, increase your distance from the light.

Is the FireLight® Bulb safe for children or pets?

Yes—with supervision. The light itself is safe, and many pets are naturally drawn to the warmth. Just make sure no one touches the bulb while it’s hot.

Always use the included protective guards with Glow and Hearth, and keep an eye on curious hands or paws.

How are FireLight® Bulbs tested before they ship?

Every FireLight® Bulb is tested not once, but twice—first at our partner facility, and again at our Missouri headquarters.

Each bulb is powered on and splash-tested while hot to ensure it can withstand thermal shock—an uncommon level of stress-testing that reveals microscopic flaws in the glass. Only the strongest, most consistent bulbs pass. Once they arrive at our facility, we inspect and test them again for visual quality, performance, and stability before they're packed for shipment.

It’s part of what makes the FireLight® Bulb different: not just the spectrum, but the standards behind the glow.

Discover Our Full Spectrum of Products

Models FireLight Infrared Sauna - Classic (4 bulbs) in Natural Color with lights on and Sauna Stool insideFireLight Sauna Hearth Quartet Infrared Sauna Panel with lights onFireLight Hearth Glow Infrared Therapy Light tilted up with light on and sitting on included basswood baseFireLight Glow
Starting Price $4,995 Trio: $1,495
Quartet: $1,995
$695
Dimensions 52in, 63in, 52in Trio: 23.75in, 15.5 in, 9 in
Quartet: 23.75in, 23.5 in, 9 in
13.5in, 7.5in, 9in
Weight 44.9 lb (20.6 kg) Trio: 7 lb (3.2 kg)
Quartet: 11.4 lb (5.2 kg)
3.6 lb (1.6 kg)
Coverage Full Full Targeted
Session Time Classic (4 bulb): 20-30 min 
SuperSauna (7 bulb) 15 min

20-30 min

Indirect Use: Unlimited

10 min on Head/Neck
10-45 min Rest of Body

Indirect Use: Unlimited

EMF-Shielded Tech
Grounding Mat N/A N/A
EMF-Blocking Enclosure N/A N/A
Warranty 10 Years 10 Years 10 Years
Portable
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The FireLight® Infrared Bulb powers the healing experience inside every SaunaSpace Glow and Hearth unit. It delivers a spectrum of red and near-infrared light designed to support detoxification, cellular repair, and nervous system regulation. Each bulb is engineered for spectral precision, thermal consistency, and safe use within SaunaSpace products.

Unlike LED red light devices, which emit narrow, flickering wavelengths, the FireLight® produces a continuous, biologically aligned spectrum without EMFs or digital interference. The result is a calming, radiant light that works with the body’s natural rhythms.

If you're beginning your light therapy journey, our SaunaSpace 101 guide offers a clear introduction to how light and heat support healing.

For a detailed look at how FireLight compares to conventional LED panels, explore our deep dive into red light therapy versus FireLight technology and learn what makes this spectrum so uniquely effective.