This lamp shade has a top diameter of 6 inches, a bottom diameter of 10 inches, and a slant height of 8 inches This attachment is called a washer attachment and is nickel in color. It is also known as a spider attachment. If your lamp has a harp, then you will generally need a washer attachment. The hole size (inner-dimension) of a washer attachment measures slightly under 1/2 inch. The drop on this particular attachment is 1/2 inch. That means, it recesses about 1/2 inch below the top of the lamp shade. Fabric exterior, translucent white styrene interior Lampshade Covering: Navy Made in USA Harp and Finial Sold Separately Is something feeling stale in your home? Try changing up your lampshades! Believe us or not, sometimes refreshing a room's look is as simple as flipping the switch on a fresh shade. This is a Washer Lampshade for Use on Desk Lamps or Table Lamps with a Harp. The inside is white styrene (white plastic).