Material specification page for precision round shims 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 988.
Why Choose A2 Stainless Steel for Precision Round Shims
The most common stainless group for indoor and general outdoor fasteners. For precision round shims, 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 Precision Round Shims 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 Precision Round Shims, the alternative stainless grade is A4 (316). A2 (304) covers general indoor and outdoor service. A4 (316) adds molybdenum, which is what buys the chloride resistance for marine and de-icing-salt exposure. Where strength matters more than corrosion, plated alloy steel in class 8.8 or 10.9 is the swap to make.
Using Stainless Fasteners in Aluminum
The galvanic couple here runs the wrong way: aluminum is the less noble metal, so it corrodes and the fastener does not. What governs the rate is the ratio of areas — a large anode and a small cathode is a tolerable combination, the reverse concentrates the attack into thin material around the hole. An isolating washer plus sealant breaks the circuit; where that is impractical, match the fastener to the substrate.
Sizes of Precision Round Shims Available in A2 Stainless Steel
| Bore d1 (mm) | Outer diameter d2 (mm) | Thickness s (mm) | Thickness tolerance (mm) | Material | Reference standard |
|---|---|---|---|---|---|
| 3 | 6 | 0.1 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 3 | 6 | 0.2 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 4 | 8 | 0.1 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 4 | 8 | 0.3 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 5 | 10 | 0.1 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 5 | 10 | 0.5 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 6 | 12 | 0.1 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 6 | 12 | 0.3 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 8 | 14 | 0.1 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 8 | 14 | 0.5 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 10 | 16 | 0.2 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 10 | 16 | 0.5 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 12 | 18 | 0.2 | +/-0.01 | 1.4310 stainless | DIN 988 |
| 12 | 18 | 0.5 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 16 | 22 | 0.3 | +/-0.02 | 1.4310 stainless | DIN 988 |
| 20 | 26 | 0.3 | +/-0.02 | 1.4310 stainless | DIN 988 |
Dimensions are independent of the material: every size above is available in A2 Stainless Steel.
Custom manufacturing · Made to drawing
Need this standoff & spacer in a grade that is not listed?
A2 Stainless Steel is one of the grades the catalog describes. A non-standard standoff & spacer is quoted from the drawing; where one already exists in the catalog, the special is usually a variation on its tooling. Made by tapping or turning.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
