Washer Lampshade for Use on Desk Lamps or Table Lamps with a Harp. By request, you may specify changes to the dimensions, covering or the hardware color. (Extra charges may be necessary.) This shade is equipped with a Washer fitter. This is the most common fitter type. It consists of a small washer with an inner diameter hole size of approximately 1/2". The washer generally rests on the top of a metal harp above the light bulb and is held in place by a screw-on finial. The inside is a white styrene (white plastic). The top and bottom of this item is adorned with a 1/2" band of single fold lampshade trim. The trim is the same color as the covering.