The most common type of base is the E type. The E stands for Edison and indicates that the base is a screw type. The size is a simple millimeter measurement of the width.

The letter “E” in E26 refers to Edison Screw, the most standard of lamp bases, while the numerical “26” refers to its diameter in millimeters (approximately 1 inch).

The three most often used bases in the United States of America for traditional lighting are the E12 (candelabra), the E26 (medium), and the E39 (mogul). Light Bulb Base Sizes Chart The Edison screw (ES) is a type of light bulb base that is universally used with electric light bulbs. Thomas Edison invented it and patented it in 1881.

E39 is known as the large base or mogul base. Its typically what is used on older metal halides and high pressure sodium from 100 watts and up. The E is for Edison screw base and the 39 is 39 mm across. Larger than the standard E26 or 26 mm across. When you buy light bulbs for a home with C-type outlets, make sure they can handle the higher operating voltages – otherwise, you risk having them blow out or catch fire if used in such fixtures. Intermediate Screw Base (E17) Bulbs are sometimes called Intermediate Edison Screw (IES), “E” stands for “Edison” and “17” indicates the diameter in millimeters as measured across the peaks of the thread on the base They are commonly used for general lighting in standard light fixtures, such as ceiling lights, lamps, can lights, outdoor spotlight and flood light fixtures, and vanity lights. However, light bulb bases are not standardized. This is to prevent dangerous light bulbs from being used in light fixtures that aren’t designed for them.Bulbs with E12 bases are commonly used for decorative applications, such as chandeliers, wall sconces, Christmas lights, restaurant pendant lights, ornamental lights, residential or commercial string lights, and night lights. Many bulbs with these bases are designed to mimic the look of a candle flame.

In North America and continental Europe, Edison screws took the place of other types of bases for general lighting. For example, a T10 wedge base is commonly used in automotive taillights, while a T15 wedge base is used in some turn signal and brake light applications. There are dozens of different light bulb bases. The most common is the Edison screw base, which may be found on most incandescent bulbs and many halogens, compact fluorescents, HIDs, and now LED lights. Edison Screw Bases This article discusses the different types of light bulb bases. It broadly covers what the different light or lamp bases mean, why different lamp bases are used for different lighting applications, and where those light bulb bases are used. Additionally, it provides a light bulb base sizes chart in shareable image format. Light Bulb Base SizesE26 is the size of most light bulbs used in the U.S. It’s referred to as having a “medium” or “standard” base. As the name suggests, the fitting is 12 millimeters in diameter size and is often deemed the Candelabra Edison Screw (CES). It is the home of C7-sized lamps, so if you bought a C7 lamp before, it utilized the E12 fitting. The biggest light bulb base is one with a diameter between 40mm and 50 mm (E39 or E40). Which is the smallest light bulb base?