CENTRIC HOME™ Flicker-Free A21 15W LED Bulb

These color temperature options correspond to the various shades of natural light. 2700K is a light color that best approximates the warm glow of traditional incandescent bulbs, while 3000K provides a bit more of a crisp and brighter white.

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, both color options feature 95 CRI and flicker-free light output, which will provide you with a healthy and relaxing environment.

Below is an article that go into further detail:

Choosing Between 2700K and 3000K

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.

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. 

Some people prefer daylight or neutral white color temperatures as they offer a more balanced spectrum that eliminates the orange and yellow tint seen in warm white color temperature bulbs.

If you're looking for a bulb that produces a crisp, energizing white light, we would recommend our CENTRIC DAYLIGHT™ product line, which offers the same 95 CRI and flicker-free performance but with daylight white color temperatures.

As with virtually all light sources, the CENTRIC HOME™ LED bulbs do emit some blue light.

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.

The CENTRIC HOME™ bulbs have a M/P ratio of approximately 0.5, which is inline with traditional incandescent and halogen bulbs.

It is also important to keep in mind that time of day, exposure time and distance away from the bulbs also have a significant influence on whether or not the blue light wavelengths will impact your circadian cycle.

We generally recommend using one bulb for every 75 square feet of space. Simply divide the square footage of your space by 75 to get the number of bulbs needed. For example, a 150 square foot area would require 150 divided by 75, or 2 bulbs.

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.

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).

These A19 bulbs have a standard screw-in base (E26 / E27), 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 A19 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.

These bulbs are currently available in an E26 base only. They can be used with global input voltages (see above), but we recommend exercising caution if used with E27 fixtures.

This product is the higher-brightness version of the CENTRIC HOME™ Flicker-Free A19 10W LED Bulb. The differences are as follows:

Brightness - this A21 bulb emits 1600 lumens, which is equivalent in brightness to a 100 watt incandescent bulb. The A19 bulb emits 800 lumens, which is equivalent in brightness to a 60 watt incandescent bulb.

This bulb emits two times the brightness compared to the A19 bulb.

(Incandescent bulb equivalence values are not exactly double, due to the fact that incandescent bulbs improve in efficiency at higher power levels).

Power - to achieve the higher brightness level, a higher electrical power input is required. As a result, the power draw for the A21 bulb is rated at 15 watts, compared to the A19 bulb which is rated at 10 watts.

The A21 utilizes ultra-efficient emitters to reach a higher luminous efficacy value, allowing us to produce twice as many lumens with only a 50% increase in power draw.

Dimensions - the A19 bulb utilizes the traditional A19 lamp size, while the A21 bulb is slightly wider and longer. For lamp fixtures with smaller lampshades, you may find that the A21 bulbs "stick out" a bit and may be an issue if such aesthetics are of concern.

The A21 bulb has a diameter of 2.76 inches (70 mm) and a length of 5.24 inches (133 mm).

CRI, color temperature and flicker - all of the color rendering, color temperature and flicker-free metrics are identical across both the A21 and A19 bulbs.