9/16"-12 x 1" Zinc Plated Steel Coarse Thread Hex Jam Nuts JNS-201 (6 pcs.)

Diameter: 9/16"
Diameter 2: 1"
Thickness: 5/16"
Material: Steel
Finish: Zinc
Driver Type: 7/8" Wrench
Thread Size: 12 (Coarse)
Shape: Jam Nut
Type: Jam Nut

Box of 6.

A jam nut is a low profile type of nut, typically half as tall as a standard nut. It is commonly used as a type of locknut, where it is "jammed" up against a standard nut to lock the two in place. It is also used in situations where a standard nut would not fit.