This 100A SPDT automotive relay is built to handle high-current switching demands in a wide range of vehicle electrical systems. Compatible with both 12V and 24V DC systems, it offers versatile performance for cars, trucks, and marine applications alike. The waterproof design ensures dependable operation even in wet or harsh under-hood environments, making it a reliable choice for engine compartments and exposed installations. Featuring a 5-pin or 4-pin SPDT configuration, this relay allows flexible switching between two circuits through a single common terminal, giving you greater control over your vehicle's electrical setup. The transparent housing lets you visually inspect the internal components, including the copper coil winding and the built-in green LED indicator that signals when the relay is active. Sturdy copper and brass terminals provide solid, corrosion-resistant connections for long-term durability. Whether you're wiring auxiliary lights, horns, fans, or other high-draw accessories, this compact and robust relay delivers the switching capacity and reliability your automotive electrical projects require.