Dimensions mm · values as the standard states them Size P s e m dw da mass G1/8 17.57 – 18
≥ 19.85
6 – 6.48
≥ 16.5
≤ 10.5
—
G1/4 20.16 – 21
≥ 22.78
—
≥ 19.1
≤ 14.2
—
G1/2 33 – 34
≥ 37.29
8 – 8.58
≥ 31.3
≤ 22.6
—
G1 45 – 46
≥ 50.85
10 – 10.58
≥ 42.8
≤ 35.9
81.3
G2 73.1 – 75
≥ 82.6
—
≥ 69.4
≤ 64.4
277
G3/8 26.16 – 27
≥ 29.56
—
≥ 24.8
≤ 18
26.1
G3/4 34 – 36
≥ 39.55
9 – 9.58
≥ 32.3
≤ 28.6
43.6
G3 102.8 – 105
≥ 116.16
—
≥ 97.7
≤ 94.9
554
G4 132.5 – 135
≥ 149.72
22 – 22.84
≥ 125.9
≤ 122
1040
(G5/8) 33 – 34
≥ 37.29
—
≥ 31.3
≤ 24.7
—
G5 162.5 – 165
≥ 183.06
22 – 22.84
≥ 154.4
≤ 149.5
1330
G6 185.4 – 190
≥ 209.5
25 – 25.84
≥ 176.1
≤ 177
1850
(G7/8) 40 – 41
≥ 45.2
—
≥ 38
≤ 32.6
54
(G11/8) 49 – 50
≥ 55.37
—
≥ 46.5
≤ 40.9
95
G11/4 53.8 – 55
≥ 60.79
—
≥ 51.1
≤ 45.3
117
G11/2 58.8 – 60
≥ 66.44
—
≥ 55.9
≤ 51.6
134
(G13/4) 68.1 – 70
≥ 76.93
13 – 13.7
≥ 64.7
≤ 58
213
(G21/4) 82.8 – 85
≥ 93.56
16 – 16.7
≥ 78.7
≤ 71
378
G21/2 92.8 – 95
≥ 104.86
—
≥ 88.2
≤ 81.2
449
Ranges read min – max; ≤ / ≥ where the standard gives one limit, ≈ for approximate values. Sizes in (brackets) are non-preferred. Select a row for its size sheet.
Size sheet · DIN 431
G1/8
s width across flats 17.57 – 18
e width across corners ≥ 19.85
m nut height 6 – 6.48
dw bearing face diameter ≥ 16.5
da transition diameter ≤ 10.5 Size sheet · DIN 431
G1/4
s width across flats 20.16 – 21
e width across corners ≥ 22.78
dw bearing face diameter ≥ 19.1
da transition diameter ≤ 14.2 Size sheet · DIN 431
G1/2
s width across flats 33 – 34
e width across corners ≥ 37.29
m nut height 8 – 8.58
dw bearing face diameter ≥ 31.3
da transition diameter ≤ 22.6 Size sheet · DIN 431
G1
s width across flats 45 – 46
e width across corners ≥ 50.85
m nut height 10 – 10.58
dw bearing face diameter ≥ 42.8
da transition diameter ≤ 35.9
mass mass per 1000 pieces (kg) 81.3 Size sheet · DIN 431
G2
s width across flats 73.1 – 75
e width across corners ≥ 82.6
dw bearing face diameter ≥ 69.4
da transition diameter ≤ 64.4
mass mass per 1000 pieces (kg) 277 Size sheet · DIN 431
G3/8
s width across flats 26.16 – 27
e width across corners ≥ 29.56
dw bearing face diameter ≥ 24.8
da transition diameter ≤ 18
mass mass per 1000 pieces (kg) 26.1 Size sheet · DIN 431
G3/4
s width across flats 34 – 36
e width across corners ≥ 39.55
m nut height 9 – 9.58
dw bearing face diameter ≥ 32.3
da transition diameter ≤ 28.6
mass mass per 1000 pieces (kg) 43.6 Size sheet · DIN 431
G3
s width across flats 102.8 – 105
e width across corners ≥ 116.16
dw bearing face diameter ≥ 97.7
da transition diameter ≤ 94.9
mass mass per 1000 pieces (kg) 554 Size sheet · DIN 431
G4
s width across flats 132.5 – 135
e width across corners ≥ 149.72
m nut height 22 – 22.84
dw bearing face diameter ≥ 125.9
da transition diameter ≤ 122
mass mass per 1000 pieces (kg) 1040 Size sheet · DIN 431
G5/8
s width across flats 33 – 34
e width across corners ≥ 37.29
dw bearing face diameter ≥ 31.3
da transition diameter ≤ 24.7 Size sheet · DIN 431
G5
s width across flats 162.5 – 165
e width across corners ≥ 183.06
m nut height 22 – 22.84
dw bearing face diameter ≥ 154.4
da transition diameter ≤ 149.5
mass mass per 1000 pieces (kg) 1330 Size sheet · DIN 431
G6
s width across flats 185.4 – 190
e width across corners ≥ 209.5
m nut height 25 – 25.84
dw bearing face diameter ≥ 176.1
da transition diameter ≤ 177
mass mass per 1000 pieces (kg) 1850 Size sheet · DIN 431
G7/8
s width across flats 40 – 41
e width across corners ≥ 45.2
dw bearing face diameter ≥ 38
da transition diameter ≤ 32.6
mass mass per 1000 pieces (kg) 54 Size sheet · DIN 431
G11/8
s width across flats 49 – 50
e width across corners ≥ 55.37
dw bearing face diameter ≥ 46.5
da transition diameter ≤ 40.9
mass mass per 1000 pieces (kg) 95 Size sheet · DIN 431
G11/4
s width across flats 53.8 – 55
e width across corners ≥ 60.79
dw bearing face diameter ≥ 51.1
da transition diameter ≤ 45.3
mass mass per 1000 pieces (kg) 117 Size sheet · DIN 431
G11/2
s width across flats 58.8 – 60
e width across corners ≥ 66.44
dw bearing face diameter ≥ 55.9
da transition diameter ≤ 51.6
mass mass per 1000 pieces (kg) 134 Size sheet · DIN 431
G13/4
s width across flats 68.1 – 70
e width across corners ≥ 76.93
m nut height 13 – 13.7
dw bearing face diameter ≥ 64.7
da transition diameter ≤ 58
mass mass per 1000 pieces (kg) 213 Size sheet · DIN 431
G21/4
s width across flats 82.8 – 85
e width across corners ≥ 93.56
m nut height 16 – 16.7
dw bearing face diameter ≥ 78.7
da transition diameter ≤ 71
mass mass per 1000 pieces (kg) 378 Size sheet · DIN 431
G21/2
s width across flats 92.8 – 95
e width across corners ≥ 104.86
dw bearing face diameter ≥ 88.2
da transition diameter ≤ 81.2
mass mass per 1000 pieces (kg) 449 Provenance
Draft — values taken from a single source and not yet cross-checked.
fasteners.eu dimensions, lengths, materials, property classes, current norm, equivalent norms Accessed 2026-09-23 · For design and safety-critical use, consult the current edition of the standard.
Data notes (1) 10 value(s) omitted after consistency checks: G1/4 m: min 67 > max 6.48 in source — min/max omitted; G3/8 m: min 8 > max 7.8 in source — min/max omitted; G5/8 m: min 9 > max 8.58 in source — min/max omitted; G7/8 m: min 10 > max 9.58 in source — min/max omitted; G11/8 m: min 11 > max 10.58 in source — min/max omitted; G11/4 m: min 12 > max 11.7 in source — min/max omitted; G11/2 m: min 13 > max 12.7 in source — min/max omitted; G2 m: min 16 > max 13.7 in source — min/max omitted; G21/2 m: min 19 > max 16.7 in source — min/max omitted; G3 m: min 22 > max 19.84 in source — min/max omitted