Parts of a Lamp Diagram – Shade, Harp, Finial, Socket, Base

All 10 parts on the diagram

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Start here: 5 main parts 5

Finial The small knob screwed onto the top of the harp. It holds the shade in place.
Shade Softens and spreads the light and hides the bare bulb. Also called the lampshade. Shade shapes include drum, empire, bell and coolie.
Harp Two metal arms that rise round the bulb from below the socket. They meet at the top, where they hold up the shade.
Bulb The bulb, which makes the light. It screws into the socket.
Base The base: the heavy body the lamp stands on, keeping it steady.

Holding the shade: 4 1

Spider fitter The spider fitter: a ring with spokes built into the shade’s frame. It sits atop the harp, held by the finial.

Light and power: 6 4

Socket The socket, which holds the bulb and connects it to the power.
Switch The switch, here a turn-knob on the socket. On some lamps it sits on the cord instead.
Cord The cord, or cable, that carries power from the wall socket.
Plug Sits on the end of the cord and fits the wall socket.

How this list was compiled: Read 2026-09-27. (1) Wikipedia, Lampshade, https://en.wikipedia.org/wiki/Lampshade : a shade reduces the light’s intensity and shields the bulb; shapes include drum, empire, bell and coolie; fabric shades have metal frames; a fitter describes how the shade connects to the lamp; the most common is the spider fitter, built into the shade frame, set atop a lamp harp and held by a finial; the harp is seated below the socket and its two arms rise round the bulb to join at the top; other fitters are clip-on and uno. (2) Wikipedia, Light fixture, https://en.wikipedia.org/wiki/Light_fixture : the light sources are in sockets; a switch on the housing or, on some portable lamps, on the power cable; movable lamps have a plug and cord for the wall socket; a shade. Licence: own work

The drawing: Drawn for this site by script, 2026-09-27. Own work, nothing traced. Licence: own work

How it works

This parts of a lamp diagram shows a table lamp front on, with the shade drawn see-through so the harp and bulb inside show. Start with the 5 main parts.

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Holding up the shade

The harp's two arms rise from below the socket round the bulb and meet at the top. The shade's spider fitter, a ring with spokes built into the shade, sits on the harp, and the finial screws on to hold it.

Light and power

The bulb screws into the socket, which has a switch on its side. The heavy base keeps the lamp steady, and the cord carries power from the plug in the wall.

To change a shade, unscrew the finial, lift the shade off the harp, and put the new one's spider fitter on top.

Questions and answers

What is the harp on a lamp?

The metal frame with two arms that rises from below the socket around the bulb and meets at the top. It holds up a shade with a spider fitter.

What is a finial on a lamp?

The small decorative knob screwed onto the top of the harp. It holds the shade's spider fitter in place.

What are the parts of a lamp shade?

The shade's covering, the frame inside it that gives it shape, and the fitter that attaches it to the lamp. Many shades also have a lining that reflects light.