Crown Bolt 19117 1/4 Inch-20 x 7/8 Inch Steel Rod Coupling Nuts, 45-Count (15 bags of 3 nuts each) Zinc-plated 1/4 inch-20 x 7/8 inch rod coupling nut For Industrial Applications 1/4-inch-20 inner diameter 7/8-inch fastener length Use with bolt of the same diameter, thread pitch, and finish