A fitter is the mechanism by which the lampshade “attaches” to the lamp.  The six most common types of fitters for a lampshade are the washer, the washer with reflector bends, the clip for a standard light bulb, the clip for a small, chandelier type of lampshade, the threaded Uno, and the Chimney:

The washer fitter is the most common lampshade fitter in the US.  It is used with a harp and finial and will work on a variety of lamps including table lamps, floor lamps and swing-arm bridge lamps.  The washer is designed to fit on top of a harp.  A harp consists of two wires that fit around the lamp socket and nest in a “harp saddle.”  The harp saddle is mounted directly below the light socket.    Once the harp is in place, the shade is mounted on top of the post, and then held in position by the finial.  Some floor lamps are designed with a reflective, white IES bowl.  The lampshade with the washer fitter that has the reflector bends, sits on top of the globe, held in place by bends or notches in the wire to keep it from sliding on the bowl.  Some table lamps (most particularly those designed with twin sockets) have a vertical rod coming up from the middle of the lamp.  The washer fitter is designed to fit over the rod, once again held in place by a finial. And, finally, the standard finish for a washer fitter is brass; however, they are also available in nickel, bronze, black, and white.

The standard bulb clip is designed to snap onto the standard incandescent light bulb (called an Edison Clip).  It is used primarily on smaller table lamps – generally those 8”, 9” and 10” shades.  The candelabra bulb clip (called a Flame Clip)  fits chandeliers and wall sconces.  The clip-on shade is made in either a full round or half round shape.  The latter type is often used on wall bracket lamps and is referred to as a “shield.” Keep in mind that any shade with a washer fitter can also be modified to use a clip fitter.

Threaded Uno fitters are 1” rings with inner threads which screw onto the end of a “no” socket on the floor or table lamp.  The uno socket varies from a standard socket only in that it has threads at the end – used to hold the uno shade fitter in place.  The uno lampshades are often used for bridge lamps in which the bulb hangs downward.

The chimney fitters are specific to lamps which hold a hurricane – a glass shade used on many oil lamps – both original oil and “electrified” oil lamps.

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