5/16"-18 Grade 8 EcoGuard® Finish Hex Nut / THREAD CLASS: 3B THREAD DIRECTION: RIGHT-HAND NUT STYLE: A12 HEXAGON NUT HEIGHT: 0.265 INCHES NOMINAL END ITEM IDENTIFICATION: 2330-01-603-3559 WIDTH ACROSS FLATS: 0.500 INCHES NOMINAL THREAD SERIES: UNC THREAD QUANTITY PER INCH: 18 NOMINAL THREAD SIZE: 0.312 INCHES BEARING SURFACE TYPE: FLAT PART NAME ASSIGNED BY CONTROLLING AGENCY: NUT, HEX MATERIAL: STEEL OVERALL SURFACE TREATMENT: ZINC OVERALL