Keep your vehicle's electrical systems running smoothly with this pack of 5 DC 12V 40-Amp 4-Pin SPST automotive starter relays. Designed as reliable replacement relays, these compact units feature copper contacts for consistent conductivity and an 80-ohm coil resistance that ensures stable, dependable switching performance. The single-pole single-throw (SPST) contact configuration delivers straightforward on/off control, making them ideal for automotive starter circuits and other 12V DC applications. Each relay operates automatically and supports a maximum switching current of 40 amps, handling demanding electrical loads with ease. The quick-connect plug-in mount design allows for tool-free installation, saving you time and effort. Measuring just 2.45" in total height, these relays are compact enough to fit in tight engine bay spaces. With a coil voltage of 12V DC and a wattage of 1.8 watts, they are well-suited for a wide range of automotive and light-duty electrical projects. Having a pack of 5 on hand means you'll always have a spare ready for multiple vehicles or future repairs. Backed by a one-year warranty for added peace of mind.