Specifying Hex Keys (Allen Keys) in A4 Stainless Steel pairs the dimensional form of Hex Keys (Allen Keys) (ISO 2936) with the engineering properties of A4 Stainless Steel. This page explains when to choose the grade, how it behaves in service, and which grades to compare it against.
Why Choose A4 Stainless Steel for Hex Keys (Allen Keys)
Specified for marine, coastal and chemical applications. For hex keys (allen keys), this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A4-80 (316) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Superior, including marine and chloride environments |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For Hex Keys (Allen Keys) in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Galvanic & Galling Considerations
Two important notes for stainless hex keys (allen keys): (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Sizes of Hex Keys (Allen Keys) Available in A4 Stainless Steel
| Wrench size s (mm) | Common bolt sizes | Short leg (mm) | Long leg (mm) | Reference standard |
|---|---|---|---|---|
| 0.7 | M1 | 28 | 51 | ISO 2936 / DIN 911 |
| 0.9 | M1.1 | 28 | 56 | ISO 2936 / DIN 911 |
| 1.0 | M1.2 | 32 | 56 | ISO 2936 / DIN 911 |
| 1.3 | M1.6 | 36 | 63 | ISO 2936 / DIN 911 |
| 1.5 | M2 | 40 | 71 | ISO 2936 / DIN 911 |
| 2.0 | M2.5 | 50 | 90 | ISO 2936 / DIN 911 |
| 2.5 | M3 | 56 | 100 | ISO 2936 / DIN 911 |
| 3.0 | M4 | 63 | 112 | ISO 2936 / DIN 911 |
| 4.0 | M5 | 71 | 125 | ISO 2936 / DIN 911 |
| 5.0 | M6 | 80 | 140 | ISO 2936 / DIN 911 |
| 6.0 | M8 | 90 | 160 | ISO 2936 / DIN 911 |
| 7.0 | --- | 100 | 180 | ISO 2936 / DIN 911 |
| 8.0 | M10 | 112 | 200 | ISO 2936 / DIN 911 |
| 9.0 | --- | 112 | 200 | ISO 2936 / DIN 911 |
| 10.0 | M12 | 125 | 224 | ISO 2936 / DIN 911 |
| 12.0 | M14 | 140 | 250 | ISO 2936 / DIN 911 |
| 14.0 | M16 | 160 | 280 | ISO 2936 / DIN 911 |
| 17.0 | M20 | 180 | 315 | ISO 2936 / DIN 911 |
| 19.0 | M22 | 200 | 355 | ISO 2936 / DIN 911 |
| 22.0 | M24 | 224 | 400 | ISO 2936 / DIN 911 |
| 24.0 | M27 | 250 | 450 | ISO 2936 / DIN 911 |
| 27.0 | M30 | 280 | 500 | ISO 2936 / DIN 911 |
| 32.0 | M36 | 315 | 560 | ISO 2936 / DIN 911 |
| 36.0 | M42 | 355 | 630 | ISO 2936 / DIN 911 |
| 41.0 | M48 | 400 | 710 | ISO 2936 / DIN 911 |
| 46.0 | --- | 450 | 800 | ISO 2936 / DIN 911 |
| 50.0 | --- | 500 | 900 | ISO 2936 / DIN 911 |
| 55.0 | --- | 500 | 900 | ISO 2936 / DIN 911 |
| 60.0 | --- | 560 | 1000 | ISO 2936 / DIN 911 |