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CENTRIC DAYLIGHT™ Full Spectrum Flicker-Free A21 15W LED Bulb

CENTRIC DAYLIGHT™ Full Spectrum Flicker-Free A21 15W LED Bulb

PART NUMBER 4006.65 | In stock

Regular price $29.00 USD
Regular price Sale price $29.00 USD
Sale Sold out
  • Available in 4000K, 5000K or 6500K
  • Completely flicker-free light output (Learn More)
  • Full spectrum, 95 CRI light quality (Learn More)
  • Compatible with global voltage input (AC90-240V/50-60Hz)
  • Conveniently screws into any standard E26 Edison socket
  • 15 Watt power consumption
  • 1600 lumens - equivalent to a 100W incandescent bulb
  • Not dimmable, not suitable for enclosed fixtures
  • 25,000 hours lifetime, 3 year warranty

Notice: This item cannot ship to California. (Why not?)

Product Description

Waveform Lighting's CENTRIC™ line of LED bulbs are now available in a super-bright 1600 lumen (100 watt equivalent) configuration! CENTRIC DAYLIGHT™ LED bulbs provides light output that is free of optical flicker and a full spectrum color that approximates that of natural daylight. If you are looking for more natural daylight but are limited by geography, season or window placement, these bulbs will give you light that is both healthy and energizing.

Flicker-free light output means that the rays of light emitted by the bulb are constant and uninterrupted, so you can rest assured knowing that the negative health effects such as headaches, fatigue and eye strain - previously associated with artificial lighting such as fluorescent lights and early LED bulbs - are eliminated.

With a 4000K/5000K/6500K 95 CRI rating and a high R9 of 80+, the light spectrum emitted by CENTRIC DAYLIGHT™ bulbs is a full and complete spectrum that provides bright, white light that matches morning sunshine (4000K), noon sunlight (5000K) or noon daylight (6500K).

Product Specifications

Color Temperature Options:

  • 4000K
  • 5000K
  • 6500K

CRI (Ra): 95+
CRI R9: 80+
Brightness: 1600 lumens (100W eq)
Voltage: AC90-240V, 50-60 Hz
Power: 15.0 watts
Installation: E26 or E27 (Medium Edison Screw)


This product is a standard A21 LED screw-in lamp designed to work in virtually all lamp fixtures, including those designed for traditional incandescent or CFL lamps.

The lamp has an industry-standard E26 base, which is the ubiquitous, approximately 1-inch wide, screw-base.

The lamp emits the equivalent brightness of a 100 watt incandescent bulb, but only consumes 15 watts. You may find that your lamp fixture has a warning regarding the maximum wattage permitted per socket. Use the 15 watt value, and not the 100 watt equivalency value, in confirming compatibility.

Pricing & Ordering Information

Listed pricing is per one bulb (1-pack) or six bulbs (6-pack). Please see below for part numbers and corresponding specifications.

PN 4006.27: 2700K
PN 4006.30: 3000K

Shipping & Returns

This item is in stock and typically ships within 1-3 business days.Shipping is free within the USA for orders over $50.

If you're not 100% satisfied with the performance, color or quality of your product, we'll work with you to make it right.

Simply contact us within 30 calendar days after delivery and we'll pay for return shipping (USA only) and offer you a full refund.

See our delivery policy,returns & refunds policy and warranty policy.

Product Disclaimers

This product is not a medical device and is not intended to diagnose, treat, cure, or prevent any disease. Read more...

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Our CENTRIC DAYLIGHT™ bulbs are offered in a range of color temperatures. 4000K provides a warmer, softer white that matches the shade of morning sunshine. 5000K has a more balanced, noon sunlight color, while 6500K provides a crisp, high-energy light similar to what you would see from a north-facing window.

All color options provide 95 CRI, full spectrum light that very closely matches natural light.


Some LED lights will produce rapid flicker or pulses that aren't immediately visible to the naked eye, which can cause headaches, nausea and eye strain. Our CENTRIC SERIES™ products include additional electrical circuitry to achieve a truly flicker-free light output that produces a comfortable and stable light level. Learn more about flicker here, or watch our video demonstration below.

Learn More

Flicker-Free Demonstration Video

Frequently Asked Questions About this Product


What is the difference between 4000K, 5000K and 6500K?

These color temperature options correspond to the various shades of natural light. 4000K is similar to the warmer and softer shade of morning sunshine. 5000K approximates the bright sun during mid-day, while 6500K is most similar to the crisp, blue color of the sky.

The choice between these colors is completely up to you! There is no correct answer, and this is a question of preference.

Regardless of your choice, all color options feature 95 CRI and flicker-free light output, which will provide you with all of the benefits of full-spectrum light.

Below are some articles that go into further detail:

Difference Between 5000K and 6500K

An In-Depth Look at 4000K

4 Things to Consider Before Buying 6500K Bulbs

Still not sure? Take advantage of our 30 day free-returns policy to try out the different colors. If you don't like it, simply let us know and we'll send over a return label.

Should I get warm white (2700K or 3000K) bulbs instead?

The most popular color temperature option for home and residential use is either 2700K or 3000K, commonly labeled warm white. These are the color temperatures that match the warm and inviting glow of traditional incandescent bulbs. 

Keep in mind that the CENTRIC DAYLIGHT™ product does not feature warm white color temperatures, but daylight white colors, designed to match natural light, and not incandescent bulb colors. You will find them to be more of a true white color, providing you with light that is crisp and energizing. You may also find that they do not "mesh" well aesthetically with other warm white bulbs in your home.

If you're looking for a bulb that produces a softer, incandescent-like glow, we would recommend our CENTRIC HOME™ product line, which offers the same 95 CRI and flicker-free performance but with warm-white color temperatures.

Are these bulbs good for visual arts, scientific or industrial applications?

These bulbs are a great fit for many applications that require a simulation of natural daylight.

For technical or visual arts applications that depend on visual assessment and a closer adherence to international standards such as D50 and D65, we recommend our NorthLux™ Series A19 LED lamps.

Do these bulbs emit blue light?

Yes, they do!

You may have read or heard about the concerns regarding the blue light hazard. Excessive blue light exposure during evening hours is certainly a concern, but blue light is an essential and important part of our daily lives, as it is extremely abundant in natural daylight (the blue sky!) and an important signal to our bodies and circadian rhythms.

CENTRIC DAYLIGHT™ bulbs are the industry's best approximation of natural daylight (95 CRI), and therefore contain similar relative levels of blue light in the spectrum as natural light.

You can think of these bulbs as mini suns that you can turn on and off at the flip of a switch. If you are concerned about blue light during evening hours and the potential impact on your sleep, we would not recommend using these bulbs at night when the actual sun has already set.

During the daytime, however, these bulbs are an excellent way to supplement or substitute for natural light.

How many bulbs should I install in my space?

We generally recommend using one bulb for every 20 square feet of space. Simply divide the square footage of your space by 20 to get the number of bulbs needed. For example, a 100 square foot area would require 100 divided by 20, or 5 bulbs.

While this may seem like a lot of brightness, do keep in mind that daylight color temperatures generally require a higher level of brightness for comfort due to a phenomenon described by the Kruithof curve.

For more guidance, we recommend checking out our lumen estimation calculator.

Are these bulbs dimmable?

Unfortunately, these bulbs are not dimmable. This means that they cannot be used on any electrical circuit which has a dimmer installed, even if you keep the dimmer at the maximum setting at all times.

Do these bulbs emit any UV radiation?

These bulbs do not emit any ultraviolet radiation. The light output covers the entire visible spectrum between 420 nanometers and 800 nanometers, but does not go below (UV-A) or above (infrared).

What kind of lamp fixture can this product be used in?

These A21 bulbs have a standard screw-in base (E26), which is the same type that has been used for more than a century.

As long as the lamp fixture is designated for an A type or A21 type, these bulbs will be compatible.

Although these lamps have the brightness of 100 watt incandescent lamps, these lamps have an actual power draw of only 15 watts. Therefore, they can safely be used in fixtures that have a max rating of less than 100 watts.

What is the voltage range of these lamps? Can they be used overseas?

The voltage range of this product is AC 90-240V and 50-60 Hz, which covers all global voltages. As such, they can safely be used internationally without any issues. The internal circuitry adjusts for the input voltage automatically, and does not affect the light output or performance of the lamp.

Customer Reviews

Based on 48 reviews
Michael Green
Great for retrofitting closets

High lumens and excellent CRI added a real kick to old dark and dingy closets. Quality light means it’s much easier to see the true colors.

Lightened up my home

I integrated these lights with my smart home setup. Everyday these lights will light up right before sunset, and it has become a moment I always look forward to.

Helped a lot in the winter when we didn't get enough daylight.

Decent Bulbs, But A Bit Expensive

The lightbulbs came in good condition, undamaged.. which is good! However the shipping speed is a bit slow for free shipping. On top of that it was a bit disappointing since Waveform Lighting is local to me (Portland/Vancouver metro area) and have HQ office and even a couple warehouses nearby.. but unfortunately you can not buy directly and you can not pick up orders locally.. So I had to wait for slow shipping from a warehouse from a different state.. weird and inconvenient.

As far as the quality of the light.. seems pretty good. But I'll admit it's a bit hard to tell without measurement equipment. To my naked eye the bulbs I got seem to have a slight pink/purple tint (ever so slight). It's almost unnoticeable on its own.. but in comparison to other bulbs becomes apparent. I also have some Philips Ultra Definition bulbs which are also 95 CRI. The Philips bulbs seem very neutral on their own. But when comparing the Philips lights almost look slightly greenish.. ever so subtly.. in contrast against the Waveform Lighting bulbs. And that's when the pinkish/purplish tint of the Waveform lights becomes a bit more apparent. So both bulbs brands seem neutral on their own.. but Philips does a little better. When comparing between the two it becomes apparent both are slightly off in different directions. Neither is perfectly in the middle neutral.. though the Philips is closer. AGAIN, this is all by eye.. no measurement equipment, so take it with a grain of salt.

Now onto price... Price is a bit high.. especially considering the Philips Ultra Definition bulbs are about a third of the price. Philips, ofcourse, does not provide any measurement data so you take them at their word.. but I've seen them measured on youtube and they stack up really well.

Lastly, I wish the Waveform Lighting bulbs came with more information/documentation and measurement data with the light bulbs themselves instead of the super basic (like generic chinese products) packaging.

Adam T
Brightened up my office

The new bulb really brightened up my office.

Jeeseob Shin
Good light bulbs

Purchased to use in my gallery and satisfied.

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