A4 Stainless Steel Toggle Latches (Draw Latches) are supplied to Trade series (over-centre toggle latches). The grade provides superior, including marine and chloride environments and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C, subject to the property class and the joint. Property data, grade comparison and the full size table follow.
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 |
