3/8"-16 Grade A Zinc Finish Steel Regular Square Nut / THREAD CLASS: 2B THREAD DIRECTION: RIGHT-HAND NUT STYLE: A15 SQUARE NUT HEIGHT: 0.310 INCHES MINIMUM AND 0.346 INCHES MAXIMUM END ITEM IDENTIFICATION: R20 SERV PLAT WIDTH ACROSS FLATS: 0.606 INCHES MINIMUM AND 0.625 INCHES MAXIMUM THREAD SERIES: UNC THREAD QUANTITY PER INCH: 16 NOMINAL THREAD SIZE: 0.375 INCHES BEARING SURFACE TYPE: CHAMFERED PART NAME ASSIGNED BY CONTROLLING AGENCY: SQUARE NUTS,ZINC PLATED MATERIAL: STEEL OVERALL MATERIAL DOCUMENT AND CLASSIFICATION: ASTM A563 GRADE A ASSN STD SINGLE MATERIAL RESPONSE OVERALL SURFACE TREATMENT: ZINC OVERALL SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: ASTM F1941 ASSN STD SINGLE TREATMENT RESPONSE OVERALL