Dimensions mm · values as the standard states them Type C Type F
Size P s e k a r y y ST2.2 3.2
3.02 – 3.2
≥ 3.38
1.3
1.18 – 1.42
≤ 0.8
≤ 0.3
≤ 2
≤ 1.6
ST2.9 5
4.82 – 5
≥ 5.4
1.5
1.38 – 1.62
≤ 1.1
≤ 0.4
≤ 2.6
≤ 2.1
ST3.5 5.5
5.32 – 5.5
≥ 5.95
2.3
2.18 – 2.42
≤ 1.3
≤ 0.5
≤ 3.2
≤ 2.5
(ST3.9) 7
6.78 – 7
≥ 7.59
2.3
2.18 – 2.42
≤ 1.3
≤ 0.5
≤ 3.5
≤ 2.7
ST4.2 7
6.78 – 7
≥ 7.59
2.8
2.68 – 2.92
≤ 1.4
≤ 0.6
≤ 3.7
≤ 2.8
ST4.8 8
7.78 – 8
≥ 8.71
3
2.88 – 3.12
≤ 1.6
≤ 0.7
≤ 4.3
≤ 3.2
(ST5.5) 8
7.78 – 8
≥ 8.71
4
3.85 – 4.15
≤ 1.8
≤ 0.8
≤ 5
≤ 3.6
ST6.3 10
9.78 – 10
≥ 10.95
4.8
4.65 – 4.95
≤ 1.8
≤ 0.9
≤ 6
≤ 3.6
(ST8) 13
12.73 – 13
≥ 14.26
5.8
5.65 – 5.95
≤ 2.1
≤ 1.1
≤ 7.5
≤ 4.2
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.
Length tolerances 4.5 3.7 – 5.3
6.5 5.7 – 7.3
9.5 8.7 – 10.3
13 12.2 – 13.8
16 15.2 – 16.8
19 18.2 – 19.8
22 21.2 – 22.8
25 24.2 – 25.8
32 30.7 – 33.3
38 36.7 – 39.3
45 43.7 – 46.3
50 48.7 – 51.3
Size sheet · DIN 7976
ST2.2
s width across flats 3.2
e width across corners ≥ 3.38
k head height 1.3
a ≤ 0.8
r fillet radius ≤ 0.3
y ≤ 2
y ≤ 1.6 Standard lengths
4.5 · 6.5 · 9.5 · 13
Size sheet · DIN 7976
ST2.9
s width across flats 5
e width across corners ≥ 5.4
k head height 1.5
a ≤ 1.1
r fillet radius ≤ 0.4
y ≤ 2.6
y ≤ 2.1 Standard lengths
6.5 · 9.5 · 13 · 16 · 19
Size sheet · DIN 7976
ST3.5
s width across flats 5.5
e width across corners ≥ 5.95
k head height 2.3
a ≤ 1.3
r fillet radius ≤ 0.5
y ≤ 3.2
y ≤ 2.5 Standard lengths
9.5 · 13 · 16 · 19 · 22 · 25
Size sheet · DIN 7976
ST3.9
s width across flats 7
e width across corners ≥ 7.59
k head height 2.3
a ≤ 1.3
r fillet radius ≤ 0.5
y ≤ 3.5
y ≤ 2.7 Standard lengths
9.5 · 13 · 16 · 19 · 22 · 25
Size sheet · DIN 7976
ST4.2
s width across flats 7
e width across corners ≥ 7.59
k head height 2.8
a ≤ 1.4
r fillet radius ≤ 0.6
y ≤ 3.7
y ≤ 2.8 Standard lengths
9.5 · 13 · 16 · 19 · 22 · 25 · 32
Size sheet · DIN 7976
ST4.8
s width across flats 8
e width across corners ≥ 8.71
k head height 3
a ≤ 1.6
r fillet radius ≤ 0.7
y ≤ 4.3
y ≤ 3.2 Standard lengths
9.5 · 13 · 16 · 19 · 22 · 25 · 32 · 38 · 45 · 50
Size sheet · DIN 7976
ST5.5
s width across flats 8
e width across corners ≥ 8.71
k head height 4
a ≤ 1.8
r fillet radius ≤ 0.8
y ≤ 5
y ≤ 3.6 Standard lengths
13 · 16 · 19 · 22 · 25 · 32 · 38 · 45 · 50
Size sheet · DIN 7976
ST6.3
s width across flats 10
e width across corners ≥ 10.95
k head height 4.8
a ≤ 1.8
r fillet radius ≤ 0.9
y ≤ 6
y ≤ 3.6 Standard lengths
13 · 16 · 19 · 22 · 25 · 32 · 38 · 45 · 50
Size sheet · DIN 7976
ST8
s width across flats 13
e width across corners ≥ 14.26
k head height 5.8
a ≤ 2.1
r fillet radius ≤ 1.1
y ≤ 7.5
y ≤ 4.2 Standard lengths
16 · 19 · 22 · 25 · 32 · 38 · 45 · 50
Provenance
Draft — values taken from a single source and not yet cross-checked.
fasteners.eu dimensions, lengths, materials, property classes, current norm, equivalent norms Otto Roth status Accessed 2026-09-23 · For design and safety-critical use, consult the current edition of the standard.
Data notes (1) The source publishes one identical table for DIN 7976, ISO 1479. Kept as the DIN table (it differs from the current ISO standard).