CROWN TRIFARI Sculpture and Textured Drop Collar Tuxedo Necklace has it's own extension piece in the back. The gold tone metal necklace is very dramatic in design, and has a flat gas pipe neck base. The removable extension is 1 inch. The necklace is approximately 17 inches closed with the extension, 16 without. It is in excellent condition. The drop is 3 by 2 inches.