Wholesale ST-4 Square Terminal with VDE Certification for High Temperature Resistance

It’s a 4mm spring terminal with a square body and PT-type interface, injection-molded around a copper galvanized core for conductivity and heat tolerance up to a point — we don’t push it past 105°C continuous in practice, though, so don’t spec it for that furnace junction box you’re building.

What it does is maintain consistent contact pressure through the spring mechanism, which basically eliminates the need for torque checks after instalation, and that’s a real time-saver when you’re terminating dozens of runs in a control panel.

We’ve got VDE approval on these, so they’ve passed the high-temp and electrcial endurance tests, but it’s worth noting they’re not suited for outdoor exposed runs — the galvanized layer holds up fine in dry indoor environments, but salt spray or condensation will accelerate corrosion faster than a plated brass alternative would.

Most buyers go with carton packaging, 500 units per box or so, and we usually have stock on the ST-4, but confirm lead time if you need over 5,000 — the injection molding tooling runs in batches, and a full MOQ of 10,000 pieces takes about 25 working days form order.

Actually, one detail you might not think to ask: teh square shape gives you a slightly larger contact surface than a round terminal of same gauge, so you’ll get a tighter tolerance on the wire insertion force — we’ve seen it reduce pull-out failures by about 15% in vibration testing compared to standard round spring terminals.

The copper galvanized material is better than plain brass for this appliction because the zinc layer doesn’t degrade the spring’s fatigue life at elevated temps, but we don’t have long-term data past 2,000 hours at 85°C, so if your use case pushes beyond that, you’ll want to run your own validation.