Dimensional standards
Understand the role of DIN, ISO, ASME, BS and EN dimensional standards when identifying a fastener.
Apply this in an RFQ →Technical library
Better fastener inquiries start with clearer specifications.
Use these technical references to organize dimensional, material, thread, coating and documentation requirements before you request a quotation.
Material grade standards
Separate product dimensions from material and mechanical property requirements such as ASTM and ISO grade designations.
Apply this in an RFQ →Metric and imperial threads
State thread diameter, pitch or threads per inch, series and fit where the requirement is controlled.
Apply this in an RFQ →Stainless steel grades
Specify 304, 304L, 316 or 316L clearly; the low-carbon L grades are included in MechBolt’s product coverage.
Apply this in an RFQ →Coatings and finishes
Select a finish according to environment, joint design, installation method and project specification.
Apply this in an RFQ →Fastener RFQ checklist
Prepare the product, standard, size, grade, finish, quantity, documentation and delivery location before requesting a quotation.
Apply this in an RFQ →Material family reference
Five commercial material families
Material family is a commercial grouping. The governing standard remains authoritative unless the customer specifies special requirements.
Mild Steel
Commercial low-carbon/general-purpose grades such as A307, F1554 Grade 36 and metric Classes 4.6/5.8.
The governing standard remains authoritative unless the customer specifies special requirements.Carbon Steel
Carbon and heat-treated structural grades such as Class 8.8, A563 nuts and hardened carbon-steel washers.
The governing standard remains authoritative unless the customer specifies special requirements.Alloy Steel
Chromium-molybdenum and high-strength alloy grades such as B7, B16, L7, A490, 10.9 and 12.9.
The governing standard remains authoritative unless the customer specifies special requirements.Stainless Steel
Austenitic stainless grades including B8, B8M, B8T, B8C, A2 and A4 families.
The governing standard remains authoritative unless the customer specifies special requirements.Other / Special Alloy
Precipitation-hardening, nickel, duplex, copper, polymer and elastomer families requiring specific supplier data.
The governing standard remains authoritative unless the customer specifies special requirements.Classification controls
Important technical distinctions
ASTM A563 Grade A
Can be supplied as hex or heavy hex depending on the mating fastener, diameter and governing product requirement.
Check the ordered nut style.ASTM A453 Grade 660
A special high-temperature precipitation-hardening bolting family, not ordinary carbon or alloy steel.
Classes A–D must remain distinct.ISO property classes
A property class defines mechanical performance; chemistry and manufacturing route may vary.
Review supplier certificate.Coatings and finishes
Finish does not change the base material family but may change nut tapping, compatibility and hydrogen-embrittlement requirements.
Review the complete assembly.Grade master
Fastener material and grade reference
Commercial reference for quotation preparation, organized by material family.
Mild Steel12 listed entries
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| Product type | Standard / specification | Grade / class | Commercial description |
|---|---|---|---|
| Hex Bolt | ASTM A307/A307M | Grade A | General-purpose low-carbon bolt |
| Heavy Hex Bolt | ASTM A307/A307M | Grade B | Flanged-joint carbon-steel bolt |
| Hex Bolt | ISO 898-1 | Property Class 4.6 | Low-strength carbon-steel bolt |
| Hex Bolt | ISO 898-1 | Property Class 5.8 | Medium-strength carbon-steel bolt |
| Threaded Rod / Stud | ASTM A307/A307M | Grade A | General-purpose carbon-steel threaded product |
| Anchor Bolt | ASTM F1554 | Grade 36 | Weldable carbon-steel anchor bolt |
| Threaded Rod / Stud | ISO 898-1 | Property Class 4.6 | General-purpose metric threaded rod |
| Threaded Rod / Stud | ISO 898-1 | Property Class 5.8 | Medium-strength metric threaded rod |
| Hex Nut | DIN 934 | Class 5 | Standard metric hex nut |
| Hex Nut | ISO 4032 | Class 5 | Standard metric hex nut |
| Steel Plate | ASTM A36/A36M | A36 | General structural carbon-steel plate |
| Steel Plate | EN 10025-2 | S275JR | General structural steel plate |
Carbon Steel14 listed entries
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| Product type | Standard / specification | Grade / class | Commercial description |
|---|---|---|---|
| Hex / Structural Bolt | ISO 898-1 | Property Class 8.8 | Quenched-and-tempered carbon or boron steel |
| Structural Bolt | ASTM F3125/F3125M | Grade A325 | High-strength structural bolt |
| Anchor Bolt | ASTM F1554 | Grade 55 | Higher-strength weldable anchor bolt when S1 is specified |
| Hex Nut | DIN 934 | Class 8 | Metric hex nut |
| Hex Nut | ISO 4032 | Class 8 | Metric hex nut |
| Hex / Heavy Hex Nut | ASTM A563/A563M | Grade A | Carbon-steel nut; style depends on application and size |
| Heavy Hex Nut | ASTM A563/A563M | Grade C | High-strength carbon-steel heavy hex nut |
| Heavy Hex Nut | ASTM A563/A563M | Grade DH | Quenched-and-tempered heavy hex nut |
| Heavy Hex Nut | ASTM A563/A563M | Grade DH3 | Weathering-steel heavy hex nut |
| Heavy Hex Nut | ASTM A563M | Class 10S | Metric structural heavy hex nut |
| Flat Washer | DIN 125 / ISO 7089 | Carbon Steel | General-purpose flat washer |
| Spring Washer | DIN 127 | Spring Steel | Split lock washer |
| Hardened Washer | ASTM F436/F436M | Type 1 | Hardened structural washer |
| Hardened Washer | DIN 6916 / EN 14399-6 | Hardened Steel | Structural washer for HV assemblies |
Alloy Steel19 listed entries
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| Product type | Standard / specification | Grade / class | Commercial description |
|---|---|---|---|
| Stud Bolt | ASTM A193/A193M | Grade B7 | Chromium-molybdenum high-temperature bolting |
| Stud Bolt | ASTM A193/A193M | Grade B7M | Restricted-hardness chromium-molybdenum bolting |
| Stud Bolt | ASTM A193/A193M | Grade B16 | Chromium-molybdenum-vanadium bolting |
| Stud Bolt | ASTM A320/A320M | Grade L7 | Low-temperature alloy-steel bolting |
| Stud Bolt | ASTM A320/A320M | Grade L7M | Restricted-hardness low-temperature bolting |
| Heavy Hex / Special Bolt | ASTM A354 | Grade BC | Quenched-and-tempered alloy-steel bolt |
| Heavy Hex / Special Bolt | ASTM A354 | Grade BD | Higher-strength quenched-and-tempered alloy bolt |
| Structural Bolt | ASTM F3125/F3125M | Grade A490 | High-strength alloy-steel structural bolt |
| Hex / Heavy Hex Bolt | ISO 898-1 | Property Class 10.9 | High-strength quenched-and-tempered bolt |
| Hex Bolt | ISO 898-1 | Property Class 12.9 | Very-high-strength quenched-and-tempered bolt |
| Heavy Hex Bolt | DIN 6914 | Grade 10.9 | High-strength structural bolt |
| Heavy Hex Nut | ASTM A194/A194M | Grade 2H | Quenched-and-tempered heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 2HM | Restricted-hardness heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 4 | Alloy-steel heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 7 | Alloy-steel heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 7M | Restricted-hardness heavy hex nut |
| Heavy Hex Nut | DIN 6915 | Class 10 | Structural heavy hex nut |
| Round Bar | AISI / SAE | 4140 | Chromium-molybdenum alloy steel |
| Round Bar | AISI / SAE | 4340 | Nickel-chromium-molybdenum alloy steel |
Stainless Steel22 listed entries
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| Product type | Standard / specification | Grade / class | Commercial description |
|---|---|---|---|
| Stud Bolt | ASTM A193/A193M | Grade B8 Class 1 | Solution-treated Type 304 stainless bolting |
| Stud Bolt | ASTM A193/A193M | Grade B8 Class 2 | Strain-hardened Type 304 stainless bolting |
| Stud Bolt | ASTM A193/A193M | Grade B8M Class 1 | Solution-treated Type 316 stainless bolting |
| Stud Bolt | ASTM A193/A193M | Grade B8M Class 2 | Strain-hardened Type 316 stainless bolting |
| Stud Bolt | ASTM A193/A193M | Grade B8T | Type 321 stabilized stainless bolting |
| Stud Bolt | ASTM A193/A193M | Grade B8C | Type 347 stabilized stainless bolting |
| Stud Bolt | ASTM A320/A320M | Grade B8 | Low-temperature Type 304 stainless bolting |
| Stud Bolt | ASTM A320/A320M | Grade B8M | Low-temperature Type 316 stainless bolting |
| Hex Bolt | ISO 3506-1 | A2-70 | Austenitic Type 304-family stainless fastener |
| Hex Bolt | ISO 3506-1 | A4-70 | Austenitic Type 316-family stainless fastener |
| Hex Bolt | ISO 3506-1 | A4-80 | Higher-strength Type 316-family stainless fastener |
| Heavy Hex Nut | ASTM A194/A194M | Grade 8 | Type 304 stainless heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 8M | Type 316 stainless heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 8MA | Strain-hardened Type 316 stainless heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 8T | Type 321 stabilized stainless heavy hex nut |
| Heavy Hex Nut | ASTM A194/A194M | Grade 8C | Type 347 stabilized stainless heavy hex nut |
| Hex Nut | ISO 3506-2 | A2-70 | Type 304-family stainless nut |
| Hex Nut | ISO 3506-2 | A4-70 | Type 316-family stainless nut |
| Flat Washer | DIN 125 / ISO 7089 | A2 / SS304 | Stainless flat washer |
| Flat Washer | DIN 125 / ISO 7089 | A4 / SS316 | Stainless flat washer |
| Steel Plate | ASTM A240/A240M | Type 304 / 304L | Austenitic stainless plate |
| Steel Plate | ASTM A240/A240M | Type 316 / 316L | Molybdenum-bearing austenitic stainless plate |
Other / Special Alloy12 listed entries
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| Product type | Standard / specification | Grade / class | Commercial description |
|---|---|---|---|
| Stud / Bolt / Nut | ASTM A453/A453M | Grade 660 Class A | Precipitation-hardening high-temperature bolting |
| Stud / Bolt / Nut | ASTM A453/A453M | Grade 660 Class B | Precipitation-hardening high-temperature bolting |
| Stud / Bolt / Nut | ASTM A453/A453M | Grade 660 Class C | Precipitation-hardening high-temperature bolting |
| Stud / Bolt / Nut | ASTM A453/A453M | Grade 660 Class D | Precipitation-hardening high-temperature bolting |
| Fastener | ASTM F468 / F467 | Brass / Copper Alloy | Nonferrous bolts and nuts |
| Fastener | ASTM F468 / F467 | Nickel Alloy / Monel | Nonferrous corrosion-resistant fastener |
| Fastener | Project / Manufacturer | Duplex 2205 | Duplex stainless fastener |
| Fastener | Project / Manufacturer | Super Duplex 2507 | Super-duplex stainless fastener |
| Washer / Seal | Manufacturer Standard | EPDM | Elastomeric washer or seal |
| Washer / Seal | Manufacturer Standard | NBR / Nitrile | Oil-resistant elastomeric washer or seal |
| Washer / Seal | Manufacturer Standard | Viton / FKM | High-temperature chemical-resistant elastomer |
| Anchor / Insert | Manufacturer Standard | Nylon | Polymer anchor component |
Important note
Dimension and grade are different controls.
Dimensional standard
Defines product geometry, dimensions, tolerances and related physical requirements—for example DIN 933 or DIN 931.
Grade or material standard
Defines material, mechanical properties, chemistry, heat treatment or testing—for example ASTM A193 Grade B7.
Project specification
May add coating, inspection, certification, marking, packing, approved manufacturer and documentation requirements.
Technical reference only
Information regarding standards, specifications, grades and applications is provided for general reference. Requirements and standard editions may change. Any discrepancy or error must be corrected against the applicable current standard, approved project specification and supplier documentation before selection or supply.