What Is A A21 Bulb

Philips 150 watt equivalent a21 dimmable with warm glow dimming effect energy saving led light bulb soft white 2700k 1 bulb model 558221 view the philips high lumen led light bulb collection.

What is a a21 bulb.

The name a21 consists of two parts the first letter and the two digit number. The a21 looks much like the a19 and both can be attached to many of the same fixtures. A 21 bulbs are twenty one 21 eighths of an inch in diameter or 2 625 inches or 66 675 millimeters. In countries that use the metric system the a21 bulbs are also referred to as the a67 bulbs where 67 refers to the diameter in millimeters.

So the light bulb that most of us have used in our homes here in the states is an a19 bulb with an e26 base. These a shape bulbs have a standard medium base that you can screw into ordinary residential light sockets and table lamps. Now a bulb s power is usually measured in lumens. A21 led light bulb a21 led light bulb specs.

The filament resists the electrical current and produces a glow incandesces. The incandescent light bulb or incandescent lamp makes light by passing electric current through a wire filament in a glass envelope filled with an inert gas. The term a21 is used to describe the overall shape and dimensions of a light bulb. What does the term a21 mean.

On the other hand the a21 bulb has larger dimensions of 2 6225 inches in diameter and 5 inches in height. A typical a19 is 2 375 inches in diameter 19 8 2 375 and 4 13 inches in height while an a21 is 2 625 inches in diameter 21 8 2 625 and about 5 inches in height. Although the size difference is negligible in most applications many buyers have been wanting to know why higher wattage household led bulbs are made in a larger size. The length of an a21 bulb is usually 105 140 mm 4 1 5 4 inches long slightly longer than the a19 bulbs.

While size may be the main and most obvious difference between the two bulbs they also have a difference in power. The a19 and a21 are pear shaped led bulbs that offer a popular alternative to incandescent bulbs. Those a shape bulbs normally have a medium bulb base which can be screwed into most residential light sockets usually in table lamps and ceiling fans. The a21 and a19 are extremely similar in appearance while a21 has a slightly longer neck and larger bulb which fits in most fixtures and occasions.

The a19 has a diameter of 2 375 inches and a height of 4 13 inches. A21 light bulbs are lesser known than their extremely popular counterpart the a19 bulb and are more commonly used for higher light output applications. By definition an a21 bulb has a diameter of about 2 6 inches. You can find led bulbs that fit that description here or other types of bulbs here.