Solid brass PLAIN 4-INCH BALL SHADE HOLDER FOR Center Draft BURNER: This fancy solid brass holder supports a 4-inch bottom ball shade. The plain rim acts as a collar that will surround the ball shade's lower lip(2-7/8" inside diameter). The center hole fits on a 4-prong Center Draft burner as is found in GWTW (Gone-with-the-Wind) type lamps, such as Royal, Bradley & Hubbard, and E. Miller.