Professional Custom Lamp Holder Accessories Manufacturer

Screw base lightbulbs such as the E26 lamp base were introduced by Edison and became widely adopted in the early 20th century. Currently, they are the most common standard in American households。Lamp Base: In the US, "medium" indicates a base that is about 1" in diameter. Synonyms for medium are "standard", "Edison" and E26. It's best to call medium "medium" or "E26" because when other bases are being discussed, the two other synonyms may cause confusion. Here in the US and elsewhere, there are other screw-thread bases that are prefixed with an "E" followed by a number indicating diameter expressed in millimeters. "Edison" is medium in the US, but only by general usage and not by any technicality, unless one is inclined to argue (probably unwisely) that E11, E12, etc., is not an acknowledgment of Edison's contribution.

Dimensions and tolerances for screw bases are standardized in ANSI standard C81.67 and IEC standard 60061-1. The two standards have mostly been harmonized, although several types exist in only one of the two standards with no equivalent in the other.The designation Exx refers to the diameter in millimeters (i.e., E26 lamp holder has a diameter of 26 mm.)