7/8″-9 x 2-1/2″ Hot Dip Galvanized Inspection Hole Coupling Nuts (3 pcs.)
Diameter: 7/8″ Length: 2-1/2″ Material: Steel Finish: Hot Dip Galvanized Driver Type: 1-1/4″ Wrench Thread Size: 9 (Coarse) Style: Inspection Hole Type: Coupling Nut Box of 3. A coupling nut is a long nut tapped from each side to meet in the middle, rather than all the way through in the same direction, used to connect two threaded rods end to end.