Fastener Identification Markings

Grade Marking Specification Material and Treatment Nominal Size (In.) Mechanical Properties Hardness Rockwell
Proof
Load
Min
(ksi)
Yield
Strength
Min
(ksi)
Tensile
Strength
Min
(ksi)
Elong % Min [9] RA % Min [10] Min Max
SAE J429 Grade 2 SAE J429
Grade 1
Low or Medium Carbon Steel 14” – 112 33 36 60 18 35 B70 B100
ASTM A307 Grade A A307
Grade A
Low or Medium Carbon Steel 14” – 4″ 60 18 B69 B100
ASTM A307 Grade B A307
Grade B
Low or Medium Carbon Steel 14” – 4″ 60 min
100 max
18 B69 B95
ASTM A307 Grade C One End Green A307
Grade C
[7]
Low or Medium Carbon Steel 14” – 4″ 36 58 min
80 max
23
ASTM F1554 Grade 36One End Blue F1554
Grade 36
Low or Medium Carbon Steel 12” – 4″ 36 58 min
80 max
23 40
ASTM F1554 Grade 55 One End Yellow F1554
Grade 55
Low or Medium Carbon Steel 12” – 2″ 55 75 min
95 max
21 30
214“- 212 21 30
234” – 3″ 21 30
314” – 4″ 21 30
SAE J429 Grade 2 SAE J429
Grade 2 [8]
Low or Medium Carbon Steel 14” – 34 55 57 74 18 35 B80 B100
78” – 112 33 36 60 18 B70 B100
ASTM A193/A320 Grade B8 A193/A320
Grade B8
Class 1
AISI SS304 Stainless No Restrictions 30 75 30 50 B96
ASTM A193/A320 Grade B8M A193/A320
Grade B8M
AISI SS316 Stainless Steel No Restrictions 30 75 30 50 B96
ASTM A325 Type 1 F3125 Grade A325 Type 1 Medium Carbon Steel, Q & T 12” – 112 85 92 120 14 35 C24 C35
ASTM A325 Type 3 F3125 Grade A325 Type 3 Atmospheric Corrosion Resistant Steel,
Q & T
12” – 112 85 92 120 14 35 C24 C35
SAE J429 Grade 5 SAE J429
Grade 5
Medium Carbon Steel, Q & T 14” – 1″ 85 92 120 14 35 C25 C34
118” – 112 74 81 105 C19 C30
ASTM A449 Type 1 A449
Type 1
Medium Carbon Steel, Q & T 14” – 1″ 85 92 120 14 35 C25 C34
118” – 112 74 81 105 C19 C30
158” – 3″ 55 58 90 B91 B100
ASTM A449 Type 3 A449
Type 3
Weathering Steel, Q & T 14” – 1″ 85 92 120 14 35 C25 C34
118” – 112 74 81 105 C19 C30
158” – 3″ 55 58 90 B91 B100
ASTM A193 Grade B7 A193
Grade B7
Medium Carbon Alloy Steel,
Q & T
14” – 212 105 125 16 50 C35
258” – 4″ 95 115 16 50 C35
418” – 7″ 75 100 18 50 C35
ASTM A354 Grade BC A354
Grade BC
Medium Carbon Alloy Steel,
Q & T
14” – 212 105 109 125 16 50 C26 C36
258” – 4″ 95 94 115 16 45 C22 C33
ASTM F1554 Grade 105 One End Red F1554
Grade 105
Medium Carbon Alloy Steel,
Q & T
12” – 3″ 105 125 min
150 max
15 45
ASTM A320 Grade L7 A320
Grade L7
AISI 4140, 4142, or 4145 14” – 212 105 125 16 50
ASTM A320 Grade L43 A320
Grade L43
AISI 4340 14” – 4″ 105 125 16 50
ASTM A490 Type 1 F3125 Grade A490 Type 1 Medium Carbon Alloy Steel,
Q & T
12” – 112 120 130 150 min
173 max
14 40 C33 C38
ASTM A490 Type 3 F3125 Grade A490 Type 3 Atmospheric Corrosion Resistant Steel,
Q & T
12” – 112 120 130 150 min
173 max
14 40 C33 C38
SAE J429 Grade 8 SAE J429 Grade 8 Medium Carbon Alloy Steel,
Q & T
14” – 112 120 130 150 12 35 C33 C39
ASTM A354 Grade BD A354
Grade BD
[6]
Medium Carbon Alloy Steel,
Q & T
14” – 212 120 130 150 14 40 C33 C39
258” – 4″ 105 115 140 C31 C39
  1. All specifications are ASTM unless otherwise noted.
  2. All specifications shall be marked by the manufacturer with a unique identifier to identify the manufacturer or private label distributor, as appropriate.
  3. Q & T – Quenched and Tempered.
  4. Although markings are shown on hex heads, stamping is a requirement on one end of rods and studs. The exception is F1554 and A307 grade C in which stamping is a supplemental requirement while color coding is required.
  5. Although markings are shown on hex heads, grade markings apply equally to products with other head configurations.
  6. All Grade BD products shall be marked “BD”. In addition to the “BD” marking, the product may be marked with 6 radial lines 60° apart.
  7. ASTM A307 grade C has been replaced by ASTM F1554 grade 36.
  8. Grade 2 requirements for diameters ranging from 1/4″ through 3/4″ only apply to headed fasteners up to and including 6″ in length, and to studs of all lengths. For headed fasteners longer than 6″, see SAE J429 grade 1.
  9. Percent Elongation
  10. Percent Reduction of Area
  11. In 2016, ASTM specifications A325 and A490 were officially withdrawn and replaced by F3125.

“-” = no requirement.