The glass shade clips into place by means of a metal spring. It can be (gently) swiveled in any direction. The pull chain can be used if a wall switch isn't present. The two slits you see above the back of the shade were originally intended for a plug-in, but the metal interior workings are absent so it can't be used as such. In excellent condition, no issues. Takes any size bulb you want to employ that fits inside the shade (a hundred wall bulb with standard base would be optimum). Two screws and it's up on the wall, or attached to an electrical box. Measurements: about 8 1/2 inches overall. The back plate has a 5-inch diameter; the shade is about 4 inches across at its widest point.