Material specification page for neoprene washers in A2 Stainless Steel. Covers the grade designation (ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to DIN 125 A.
Why Choose A2 Stainless Steel for Neoprene Washers
The most common stainless group for indoor and general outdoor fasteners. For neoprene washers, this matters when good general corrosion resistance is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Good general corrosion resistance |
Corrosion Behavior in Service
A2 (304) gives excellent atmospheric and most-water corrosion resistance and is the most common stainless for Neoprene Washers in indoor and general outdoor service. In chloride-bearing environments (marine air, road salt, swimming pools) consider stepping up to A4 (316).
Comparable Grades
For Neoprene Washers, the alternative stainless grade is A4 (316). The practical dividing line is chlorides: A2 (304) is fine until salt is involved, and A4 (316) exists for the cases where it is — coastal, marine and road-salt service. Neither reaches the strength of a plated class 8.8 or 10.9 fastener.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so with an electrolyte present — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. Area ratio decides how bad it gets: a small stainless fastener in a large aluminum section is normally acceptable, a large stainless fastener in thin aluminum is not. Where the joint gets wet, isolate the metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Neoprene Washers Available in A2 Stainless Steel
| Thread size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness s (mm) | Hardness (Shore A) | Temperature range (deg C) | Reference standard |
|---|---|---|---|---|---|---|
| M3 | 3.2 | 7 | 1.0 | 60 | -35 to +100 | DIN 125 A series |
| M4 | 4.3 | 9 | 1.5 | 60 | -35 to +100 | DIN 125 A series |
| M5 | 5.3 | 10 | 1.5 | 60 | -35 to +100 | DIN 125 A series |
| M6 | 6.4 | 12 | 2.0 | 60 | -35 to +100 | DIN 125 A series |
| M8 | 8.4 | 16 | 2.0 | 60 | -35 to +100 | DIN 125 A series |
| M10 | 10.5 | 20 | 3.0 | 60 | -35 to +100 | DIN 125 A series |
| M12 | 13 | 24 | 3.0 | 60 | -35 to +100 | DIN 125 A series |
| M16 | 17 | 30 | 3.0 | 60 | -35 to +100 | DIN 125 A series |
Dimensions are independent of the material: every size above is available in A2 Stainless Steel.
Custom manufacturing · Made to drawing
Need this washer in a grade that is not listed?
A2 Stainless Steel is one of the grades the catalog describes. Bearing area is usually the reason for a special washer: a larger outside diameter to spread load into a softer material, or a thicker section to resist dishing. Made by stamping or punching.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
