A4 Stainless Steel (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80) is specified for marine, coastal and chemical applications. Specified on toggle latches (draw latches) it determines the corrosion behaviour (superior, including marine and chloride environments) and the service temperature range (approx. -200 °C to +400 °C, subject to the property class and the joint); the dimensions are ours rather than a standard's, and are listed in full below.
Why Choose A4 Stainless Steel for Toggle Latches (Draw Latches)
Specified for marine, coastal and chemical applications. For toggle latches (draw latches), this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| 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 Toggle Latches (Draw Latches) in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Galvanic & Galling Considerations
For stainless toggle latches (draw latches) the compatibility question is galvanic rather than galling: joined to aluminum or galvanized steel in wet service, stainless drives corrosion of the less-noble metal. Isolate with a coating, sleeve or non-conductive washer where the joint sees moisture. Note also that stainless is softer than hardened carbon steel, so where the part carries a wear or shear duty, check the load against the grade before substituting.
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 Toggle Latches (Draw Latches) Available in A4 Stainless Steel
| Form | Adjustment | Locking | Typical use |
|---|---|---|---|
| fixed-hook toggle latch | none | over-centre | cases, covers, panels |
| adjustable-bail toggle latch | threaded bail | over-centre | gasketed covers needing set compression |
| toggle latch with safety catch | threaded bail | over-centre plus secondary catch | vibration and transport |
| padlockable toggle latch | threaded bail | over-centre, padlock hasp | secured enclosures |
| stainless toggle latch | threaded bail | over-centre | washdown and marine |
Dimensions are independent of the material: every size above is available in A4 Stainless Steel.
Custom manufacturing · Made to drawing
Need this panel latch in a grade that is not listed?
A4 Stainless Steel is one of the grades the catalog describes. The geometry is whatever the drawing says. A machined component has no standard to depart from, so the drawing and the tolerance scheme are the whole specification. Made by stamping or punching.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
