1/4"-20 x 7/16" x 1-3/4" Zinc Rod Coupling Nuts (12 pcs.)

Diameter: 1/4"
Diameter 2: 7/16"
Length: 1-3/4"
Material: Steel
Finish: Zinc
Driver Type: 7/16" Wrench
Thread Size: 20 (Coarse)
Style: Hex
Type: Coupling Nut

Box of 12.

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.