Edison screw , ES (abbreviation)

It has a pear-like shape and an Edison screw base.

In many other countries the Edison screw (E) base is used for lighting.

The medium Edison screw has seven threads per inch, or about 3.6mm per thread.

Edison screw fittings are not as common, but may be found on some imported lighting equipment, particularly from Southern Europe.

Most Edison screws have a right-hand threading that tightens when the lamp is turned clockwise.

Medium Edison screw (MES) bulbs for 12 V are also produced for recreational vehicles.

Edison screw lampholder adaptors (for NEMA 1-15 plugs) are still easily found and commonly used in the Americas.

Today most incandescent lamps for general lighting service use an Edison screw in candelabra, intermediate, or standard or mogul sizes, or double contact bayonet base.

These usually come with an Edison screw (ES) connection, rather than the more common bayonet cap (BC) with the two familiar side pins.

The bulb is inserted and removed with straight in or out force, without turning as with a bayonet mount or Edison screw, on certain bi-pin light sockets.

The Edison screw base became popular and eventually displaced competing standards for lamp bases for general lighting purposes in several places, especially in North America and continental Europe.

The Edison screw socket was used as an outlet (such as for toasters) when mains electricity was still mainly used for lighting, and before wall outlets became common.

The cost of a CFL with a GU24 fitting is approximately equal to a CFL with an Edison screw fitting.

In the U.S., the Energy Independence and Security Act of 2007 requirement for greater energy efficiency only applies to the medium Edison screw, all other being considered "specialty" lamps.

A GU24 connector is fitting for compact fluorescent light bulbs (CFL) that uses a bayonet mount bi-pin connector instead of the Edison screw fitting used on many incandescent light bulbs.

The GU24 fitting is not compatible with older light fixtures designed for incandescent bulbs, whereas a CFL with an Edison screw fitting is a direct replacement for an incandescent bulb.

Some adapters for wall outlets use an Edison screw, allowing a light socket to become an ungrounded electrical outlet (such as to install Christmas lights temporarily via a porch light), or to make a pull-chain switch with two outlets, or to split it for two lamps.

On September 24, 2009 the DOE announced that Philips Lighting North America was the first to submit lamps in the category to replace the standard 60 W A-19 "Edison screw fixture" light bulb, with a design based on their earlier "AmbientLED" consumer product.

French plugs that need to be polarized are configured in such a way as to only be inserted correctly in grounded sockets, however the old 2 pin socket is inherently dangerous with equipment that should be polarized for example table lamps with a cord switch and Edison screw lamp.