Metric Property Class 4.8
Class 4.8 is close to 4.6 in tensile but has a higher yield ratio. Common on commodity metric hardware.
| Marking | 4.8 plus manufacturer ID (required from M5 on marked products) |
|---|---|
| Matching nut | ISO 898-2 class 5 |
Mechanical properties (ISO 898-1)
| Class | Tensile Rm (min) | Yield (min) | Proof stress | Hardness |
|---|---|---|---|---|
| 4.8 | 420 MPa | 340 MPa | 310 MPa | 130 - 220 HV |
These tables carry the same figures as the printed sheet below.
The printed sheet

See an error on this sheet?
Tell us what is wrong.
Text version of this sheet
ISO 898-1 · property class 4.8 · low strength, higher yield ratio
FIELD IDENTIFICATION
What it is
Class 4.8 is close to 4.6 in tensile but has a higher yield ratio. Common on commodity metric
hardware.
MFG
4.8
Marking
4.8 plus manufacturer ID (required from M5 on marked products)
Matching nut
ISO 898-2 class 5
Head stamped 4.8 + manufacturer ID
Mechanical properties (ISO 898-1)
Class
Tensile Rm (min)
4.8
Yield (min)
420 MPa
Proof stress
340 MPa
Hardness
310 MPa
130 - 220 HV
Key points
Often cold-formed without heat treatment.
Governing standards: ISO 898-1:2013; ISO 898-2:2022. Editions shown are the latest confirmed as of September 2026. The drawing and the governing standard always take
precedence over this sheet.
torquing any fastener. Verify the current governing standard, project documents, OEM requirements, size, thread, coating and lot certification. To the fullest extent permitted by law, The Fastener App disclaims liability
arising from reliance on this reference.
Fastener Guide reference FG-5B7FF7 · thefastenerapp.com/fastener-guide/technical-reference/metric-property-class-4-8 · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.

























