Struggling to decode fastener part numbers or spec sheets?
Fastener part numbers may look confusing, but once you understand the format, they reveal everything you need to know:
- Size
- Thread
- Length
- Coating
- Strength grade
- Head type
Let’s break it down…
Example part number: 12X75M8.8ZPB > M12 75 PC8.8 Zinc Hex Bolt
1. Diameter:
- M12 = 12mm metric thread diameter
2. Length:
- 75 = 75mm overall length (measured from under the head for hex bolt)
3. Grade/Property Class:
- PC 8.8 = High tensile strength, compliant with ISO 898-1 (grade is imperial, property class is metric)
4. Finish:
- ZP = Zinc Plated (could also be G304, G316, SS for Stainless Steel)
5. Head/Drive style:
- HEX = Hexagonal head (alternatives include CSK for countersunk, SHCS for socket head cap screw)
6. Fastener type:
- BOLT = Type of fastener (could also be SCREW, STUD, ANCHOR, etc.)
Common abbreviations and codes
|
Code |
Meaning |
|
|
M |
Metric |
|
|
UNC |
Unified National Coarse Thread (USA inches system) |
|
|
UNF |
Unified National Fine Thread (USA inches system) |
|
|
BSW |
British Standard Whitworth |
|
|
ZP |
Zinc Plated |
|
|
HDG |
Hot-Dip Galvanised |
|
|
G304, G316, SS |
Stainless Steel (A2 or A4) |
|
|
CSK |
Countersunk |
|
>> Download our materials and finishes PDF
Standards you might see
Fasteners are often labelled with the applicable product standards:
AS 1110.1 Hexagon head bolts
AS/ NZS 1252.1 High Strength Steel fastener assemblies for structural engineering
ISO 898:1 Mechanical properties of fasteners made of carbon steel and alloy steel- bolts, screws and studs
EN 14399-3 High-strength structural bolting assemblies for preloading- System HR
These help with procurement or matching to engineering specifications.
>> Download our Australian standards PDF
Tip: Check standard and specifications
For critical applications, check fastener standards and specifications that includes:
- Dimensional characteristics
- Thread pitch
- Material grade and mechanical properties
- Surface treatment specification
- Compliance certificates (e.g. Inspection Certificates)
Save time with our team
At United Fasteners, we help procurement teams and engineers:
- Match part numbers to stocked SKUs
- Custom-label kits and pallets
- Convert drawings into order-ready items
Need help decoding a spec sheet or quote? Send us your BOM or drawing and we’ll take care of the rest.