ISO 7089 Flat Washer Specifications
ISO 7089 Flat Washers
DIN 125A Equivalent | Standard Metric Flat Washers — Grade A
ISO 7089 defines the standard flat washer for metric fasteners — Grade A with normal series dimensions. These washers distribute load, protect surfaces, and provide a smooth bearing surface for bolt heads and nuts.
Quick Specifications
Type
Flat (Plain)
Product Grade
Grade A
Series
Normal
DIN Equivalent
DIN 125 Form A
Dimensions
| For Bolt | Inner Dia. (d1) | Outer Dia. (d2) | Thickness (h) |
|---|---|---|---|
| M5 | 5.3 mm | 10 mm | 1.0 mm |
| M6 | 6.4 mm | 12 mm | 1.6 mm |
| M8 | 8.4 mm | 16 mm | 1.6 mm |
| M10 | 10.5 mm | 20 mm | 2.0 mm |
| M12 | 13.0 mm | 24 mm | 2.5 mm |
| M16 | 17.0 mm | 30 mm | 3.0 mm |
Materials
Zinc Plated Steel
Most common
A2 Stainless
304 grade
A4 Stainless
316 marine grade
Hot-Dip Galvanized
Outdoor structural