Lamp finials are threaded 1/4-27 to fit standard lamp harps Secures lampshade to standard table or floor lamps Finial Dimensions: 2.5" x 1.5" (Height x Width) Great way to update the style of any lamp. Finish the look of your lamp and add a touch of style with Royal Designs, Inc. Brass Finials. Whether you desire a simple and inexpensive update, or are restoring an antique lamp, Royal Designs finials provide that finishing touch. Finial finishes come with a protective lacquer coating which protects the finials against discoloration and tarnishing and will not require polishing. All RDI finials are female threaded individually to fit standard harps. Easy to install, unplug your lamp and remove the old finial by turning counterclockwise. Then, place the lampshade over the lamp harp's threaded stud and fasten the finial by turning clockwise.