PRODUCT SPECIFICATIONSPart #: 0000-116851Fastener Type: Finished Hex NutSize Description: 9/16"-18Diameter/Nominal Size: 9/16"Thickness: 31/64" (0.473-0.496")Wrench Size/Across Flats: 7/8" (0.861-0.875")Width Across Corners: 0.982-1.010"Thread Pitch: 18Thread Pitch Type: FineThread Direction: RightSystem of Measurement: InchGrade: 2Material: Low Carbon SteelFinish: Zinc PlatedDrive Type: External HexUsed with: Bolts/Screws up to Grade 5Average Piece Weight: 0.0569800 lbs.Nuts are almost always used in conjunction with a mating bolt to fasten multiple parts together; kept together by a combination of their threads' friction, a slight stretching of the bolt, and compression of the parts to be held together.