An "A" bulb has the classic light bulb shape, commonly compared to an upside-down pear. The two digits after the letter refer to the bulb's diameter at its widest point, and is measured in eighths of an inch. An A19 bulb, therefore, has a diameter of 19 divided by 8 inches, or approximately 2.4 inches.

Ring's Smart LED Lightbulbs are part of Ring's Smart Lighting line of products that offer you all new ways to customize your security and internal lighting - everything from security floodlights to porch lights - to maximize both comfort and security.

The A19 is a more universally applicable bulb that mimics the 'classic' bulb shape. The dispersed lighting from the curved shape makes the A19 bulb better suited to floor lamps and hanging ceiling fixtures.

So if you have multiple light bulbs you can set it up as a group so you can turn them on and off. All together at the same. Time. Now of course this is a smart light bulb.

A19 refers to the shape and size of the bulb itself. "A" stands for Arbitrary -- just the name of the shape that's familiar to most of us. "19" refers to the size -- in this case, 19/8" (or 2 3/8") across. E26 refers to the type and size of the base -- the part that goes into the light socket.

What is an A19 Bulb? The most common type of bulb used in homes today is the A19. It gets its name because it has a rounded pear shape (an "A" - or arbitrary - shape) and its base measures 19 mm across. It has a medium-sized screw mount that fits into a standard socket.

A ring light (sometimes known as a “ring flash”) is a round, electronic source of light that sits around a camera lens and offers even, diffused, shadowless illumination of a subject. Additionally, they have several small bulbs (as opposed to one large bulb, like traditional flashes) that work to blur imperfections.

The ring lights main purpose is to cast an even light onto the subject. This reduces shadows in the face and minimizes blemishes, while illuminating the eyes. This is why ring lights are commonly used in portraits, glamour shots, or even videography capturing only one subject.

What is A19? A19 is a term that describes the overall shape and size of a light bulb. Specifically, the bulb should be roughly pear-shaped , and have a length of 100-110 mm and a width of approximately 60 mm.

Arbitrary A19 refers to the shape and size of the bulb itself. "A" stands for Arbitrary -- just the name of the shape that's familiar to most of us. "19" refers to the size -- in this case, 19/8" (or 2 3/8") across. E26 refers to the type and size of the base -- the part that goes into the light socket.

What is A19? A19 is a term that describes the overall shape and size of a light bulb. Specifically, the bulb should be roughly pear-shaped , and have a length of 100-110 mm and a width of approximately 60 mm.

Smart lights are Wi-Fi-enabled devices that connect to the internet using wireless networks. Certain smart light bulbs require a dedicated smart hub to connect with wirelessly, with the hub then plugging into an internet router. The hub also acts as a gateway between the smart light and your phone or tablet.