Nut Compatibility Chart

Grade of BoltSurface FinishNominal Size InchesA563 Grade and ANSI Nut Style
RecommendedSuitable
HexHeavy HexHexHeavy Hex
A307 Grade A & C
Any1⁄4 to 11⁄2
A
B,D,DH
A,B,C,D,DH,DH3
>11⁄2 to 2
A
A
C,D,DH,DH3
>2 to 4
A
C,D,DH,DH3
A307 Grade B
Any1⁄4 to 11⁄2
A
B,D,DH
A,B,C,D,DH,DH3
>11⁄2 to 2
A
A
>2 to 4
A
F3125 A325 Type 1
Plain1⁄2 - 11⁄2
C
C3,D,DH,DH3
Galvanized1⁄2 - 11⁄2
DH
F3125 A325 Type 3
Plain1⁄2 - 11⁄2
C3
DH3
A354 Grade BC
Plain1⁄4 to 11⁄2
C
D,DH
C3,D,DH,DH3
>11⁄2 to 4
C
C3,D,DH,DH3
Galvanized1⁄4 to 11⁄2
DH
>11⁄2 to 4
DH
A354 Grade BD
Plain1⁄4 to 11⁄2
DH
DH
D,DH,DH3
>11⁄2 to 4
DH
DH3
A449
Plain1⁄4 to 11⁄2
B
D,DH
B,C,C3,D,DH,DH3
>11⁄2 to 3
A
C,C3,D,DH,DH3
Galvanized1⁄4 to 11⁄2
DH
D,DH
D
>11⁄2 to 3
DH
D
F3125 A490 Type 1
Plain1⁄2 - 11⁄2
DH
DH3
F3125 A490 Type 3
Plain1⁄2 - 11⁄2
DH3
A687
Plain5⁄8 - 3
D
DH,DH3
Galvanized5⁄8 - 3
DH
F1554 Grade 36
Any1⁄2 to 11⁄2
A
B,D,DH
A,B,C,D,DH,DH3
>11⁄2 to 4
A
C,D,DH,DH3
F1554 Grade 55
Plain1⁄2 to 11⁄2
A
B,D,DH
A,B,C,D,DH,DH3
>11⁄2 to 4
A
C,D,DH,DH3
Galvanized1⁄2 to 4
A
C,D,DH,DH3
F1554 Grade 105
Plain1⁄2 to 11⁄2
D
DH,DH3
>11⁄2 to 3
DH
DH3
Galvanized1⁄2 to 3
DH
DH3
1. Nuts made in accordance with the requirements of Specification A194 Grade 2H and marked with its grade symbol are an acceptable equivalent for Grade DH nuts. (per ASTM A563/A563M-21a, Table X1.1)

ASTM A194 Nut Compatibility Chart

Grade of BoltA194 Heavy Hex Nut Grade
A193 Grade B72H or 4 or 7
A193 Grade B8 (Class 1 and 2)8
A193 Grade B8M (Class 1 and 2)8M
A320 Grade L74 or 7
A320 Grade B8 (Class 1 and 2)8
A320 Grade B8M (Class 1 and 2)8M
A320 Grade B8C8C
A320 Grade B8T8T
A320 Grade B8LN8LN
A320 Grade B8MLN8MLN
For Class 2 stainless steel grades, strain hardened nuts available as a supplementary requirement