1/4-20 Grade 2 Polished Chrome Plated Acorn Nut / THREAD DIRECTION: RIGHT-HAND NUT STYLE: A10 CAP NUT HEIGHT: 0.590 INCHES NOMINAL END ITEM IDENTIFICATION: 3930015999978 WIDTH ACROSS FLATS: 0.437 INCHES NOMINAL THREAD SERIES: UNC NOMINAL THREAD SIZE: 0.250 INCHES PART NAME ASSIGNED BY CONTROLLING AGENCY: ACRON NUT SPECIAL FEATURES: IMPERIAL;POLISHED CHROME PLATED;CAP DIAMETER 0.410 MATERIAL: STEEL OVERALL MATERIAL DOCUMENT AND CLASSIFICATION: ASME B1.1 UNC/UNF CL2B NATIONAL STD/SPEC 1ST MATERIAL RESPONSE OVERALL AND ANSI B1.1 UNC NATIONAL STD/SPEC 1ST MATERIAL RESPONSE NONDEFINITIVE SPEC/STD DATA: 2 GRADE AND 0.338 WEIGHT