Your solar array's been running and you know one bad connection in the sun is all it takes to start a slow oxidation problem. This MC4 connector is built for exactly that. 4mm female, waterproof, rated for 30A at 70°C. Tin-plated contacts keep resistance under 5 milliohms so your current isn't bleeding off as heat. TUV certified to 2 PfG 1161/01.06. Pair it with Jaycar's WH-3120 or WH-3122 solar cables and you've got a connection that doesn't need checking every season. Add to cart and lock in a connection that holds