1/2"-13 Grade 18-8 Stainless Steel Top Lock Nut / THREAD CLASS: 2B THREAD DIRECTION: RIGHT-HAND NUT STYLE: A12 HEXAGON NUT HEIGHT: 0.427 INCHES MINIMUM AND 0.573 INCHES MAXIMUM END ITEM IDENTIFICATION: 2320-01-564-6882 TRUCK TRACTOR WIDTH ACROSS FLATS: 0.736 INCHES MINIMUM AND 0.752 INCHES MAXIMUM THREAD SERIES: UNC THREAD QUANTITY PER INCH: 13 NOMINAL THREAD SIZE: 0.500 INCHES PART NAME ASSIGNED BY CONTROLLING AGENCY: TOP LOCK NUT MATERIAL: STEEL CORROSION RESISTING OVERALL SURFACE TREATMENT: PASSIVATE OVERALL SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: ASTM A380 ASSN STD SINGLE TREATMENT RESPONSE OVERALL