The Heavy Duty 30-amp Horn Relay is a practical and reliable solution for your vehicle's horn or fog lamps. With its 12 Volt Four Terminal design and black plastic waterproof case, this relay is built to withstand tough conditions. It can be used with all Wolo Air Horns and fits most makes and models. Whether you need to replace a faulty relay or upgrade your existing one, this Heavy Duty Horn Relay is the perfect choice. Its 30-amp capacity ensures optimal performance, making it a must-have for any 30-amp circuit.